CBR - 2016 (67) PROFICIENCY TESTING PROGRAM REPORT · Report This report is available on the LabSmart Services website. The issue of this proficiency report was ... CBR Proficiency

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CBR - 2016 (67)

PROFICIENCY TESTING

PROGRAM REPORT

Accredited for compliance with ISO/IEC 17043

Copyright: LabSmart Services Pty Ltd

CBR Proficiency Testing Program - 2016(67)

Copyright: LabSmart Services Pty Ltd Report Issued - February 2017 Page 1 of 80

Report This report is available on the LabSmart Services website. The issue of this proficiency report was authorised by Peter Young, Director, LabSmart Services Pty Ltd, February 2017. Contact Details

Email: [email protected] Mobile: 0432 767 706 Fax: (03) 8888 4987

Program Coordinator The program coordinator for this program was Peter Young, Director, LabSmart Services Pty Ltd. Contact Details

Email: [email protected] Mobile: 0432 767 706 Fax: (03) 8888 4987

Accredited Proficiency Testing Provider LabSmart Services is accredited by NATA to ISO/IEC 17043, Conformity assessment – General requirements for proficiency testing. Accreditation number 19235. The accreditation provides additional assurance to participants of the quality and importance we place on our proficiency testing programs.

LabSmart Services As well as proficiency testing programs LabSmart Services also offers a wide range of other services including consultancy, training and nuclear gauge calibration. Please see our website for further details.

www.labsmartservices.com.au

Copyright This work is copyright. No part of this publication may be reproduced in any form, transmitted or stored in any repository (e.g. mechanical, digital, electronic or photographic) without prior written permission of LabSmart Services Pty Ltd. Please contact LabSmart Services should you wish to reproduce any part of this report.

Amendment History Reports may be downloaded from the LabSmart Services website.

Version 1 – Issued 28 February 2017



CONTENTS PAGE

1. Program Aim

5

2. Performance

2.1 Performance assessment 2.2 Identified outliers 2.3 Focus on improvement 2.4 Program summary

5 5 6 6 9

3. Technical Comment

3.1 General performance

3.1.1 Supply of program information 3.1.2 Errors

3.2 Statistical reality

3.2.1 Accuracy of data 3.2.2 Variation in CBR results 3.2.3 Set s.d limit 3.2.4 Repeatability

3.3 CBR results

3.3.1 Participant assessment 3.3.2 CBR results 3.3.3 Identification of inconsistencies and errors 3.3.4 Repeatability

3.4 Measurement uncertainty 3.5 Direct influences

3.5.1 Load cell 3.5.2 Seating load 3.5.3 Penetration rate 3.5.4 Test (penetration / load) data 3.5.5 Accuracy of the graph prepared 3.5.6 Zero-point correction 3.5.7 Rounding

3.6 Indirect influences

3.6.1 Pre-compaction curing 3.6.2 CBR compaction 3.6.3 OMC & MDD 3.6.4 LDR & LMR

3.7 Test method

11

11

11 12

12

12 13 13 14

14

14 15 15 16

17

19

19 20 21 23 24 25 27

29

29 29 31 31

33

4. Statistics: Z-Scores & Graph

4.1 CBR Z-scores : Sample A & B 4.2 Recalculated CBR results 4.3 Repeatability 4.4 Set SD limits

36

35 39 43 45



5. Program Information

5.1 Z-score summary 5.2 Program design

5.2.1 Design 5.2.2 Selection of material for program 5.2.3 OMC & MDD 5.2.4 Role of proficiency testing 5.2.5 Participant assessment 5.2.6 Reporting of results – significant figures 5.2.7 Additional information requested

5.3 Sample preparation 5.4 Packaging and instructions 5.5 Quarantine 5.6 Sample dispatch 5.7 Homogeneity testing 5.8 Participation 5.9 Statistics

5.9.1 Z-score Summary 5.9.2 Comparing statistics from one program to another 5.9.3 Measurement uncertainty 5.9.4 Metrological traceability

47

47 47

47 47 48 48 48 49 49

49 49 50 50 50 50 50

52 52 53 53

6. Participants’ Test Results

55

Appendix A Instructions for testers

Appendix B Results log

Appendix C Graph example

75

77

80



1. Program Aim

The proficiency program was conducted in September/October 2016 with participants

throughout Australia. The program involved the performance of:

AS 1289.6.1.1 (2014) – Determination of the California Bearing Ratio of a soil –

Standard laboratory method for a remoulded specimen.

The program’s intention is to provide feedback and confidence to the construction

materials testing industry regarding the competency of participants (and the industry)

to perform this test. Each participant’s performance is statistically assessed and used

as a measure of competency relative to all those who participated. Other measures

of performance are also used.

This report has been prepared using robust statistics. In addition, test data has been

reviewed for consistency and additional feedback regarding aspects of the test are

provided.

Comprehensive technical comment is provided to assist participants improve the

overall performance of this test (Section 3).

Information regarding the conduct and design of the program etc. can be found under

section 5.

2. Performance

2.1 Performance assessment The CBR test is a complex test from a measurement uncertainty perspective despite its apparent technical simplicity. Unfortunately, the CBR test method does not provide guidance about some aspects of the test such as reproducibility. There also appears a lack of guidance on both the performance and the interpretation of the test within the industry. The range of test results obtained in a proficiency program, for any given sample, has been far wider than is generally acceptable to the industry. These aspects add to the difficulty in interpreting CBR proficiency programs. In discussing the outcome of this program the following have broadly been used to determine outliers and areas for investigation/review.

Z-scores based on submitted CBR results (statistical outliers)

Identification of inconsistences, non-adherence to test method and errors

Accuracy of calculations

Repeatability Proficiency testing providers are obligated under their accreditation standard to remove results known to be incorrect or where a participant has not followed the test method including adherence to prescribed limits. Not providing all data requested,



particularly where it is used to assess the validity of the results obtained (e.g. compaction, MC) is also a valid reason to reject a CBR result. This is not however ‘black & white’ but where the ‘grey area’ becomes complex. Keeping results that may be suspect in the statistical pool may distort the statistical outcome. However, if all the results found to be inaccurate or not meet the test method etc. were rejected form this program there would be very little to analyse! A balance must be struck. This is discussed in more detail under technical comment (section 3.1 & 3.2).

2.2 Identified outliers

In most proficiency testing programs the identification of outliers is relatively straight

forward. This is not the situation with CBR testing due to the large range in CBR

results obtained.

Industry has expressed concerns that from an engineering “End User” perspective that

such large variations in CBR results are impractical. It is also undesirable from a

laboratory testing perspective.

As has been indicated in previous proficiency programs, it is the middle 50% of

participants results that is far larger than it should be. It is this group of results

therefore that is of primary interest.

Participants with statistical outliers, departure from the test method or errors

(Investigate) and those with significant departures compared to other participants

(Review) are shown in table 2.2A.

Participants where there is a concern regarding accuracy of the results are requested

to investigate their submissions. Others have been identified as able to benefit from

reviewing their submissions where it is felt the quality of testing may be improved.

In table 2.2A there are no participants listed e.g. ‘penetration rate’ and ‘test data’. This

is not because there are no concerns identified only that the test method does not

identify or address the issues affecting accuracy identified in this program.

The more times a participant’s code appears in the table 2.2A the greater the need for

follow up.

2.3 Focus on improvement Have laboratories improved? The answer is yes. The standard of CBR testing has

improved enormously over the last 5 to 7 years. Much of this can be attributed to

laboratories being prepared to participate in PT programs and being prepared to

improve on existing laboratory practices (e.g. move away from hand graphs to

computer generated graphs etc.).



Area Section Investigate Review

CBR results 3.3.2 V5, S7 -

Repeatability 3.3.4 F2, U7, R5, V5, S7, X3 -

Load cell 3.5.1 - Z6, W8, J7, X6, Z3, Y3 & M3

Seating load 3.5.2

M8, D8, U9, T9, L8, Z6, F2, W8, J7, B8, S6, T2, Y9, A2, X6, R5, N8, U3, S7, M4, U3, E9, J8, A3, K2, N3, L7, N9, X3, N5, Z3, P6, C4, Y3, Q5, C2, E4, M3, R6, G2, R7

-

Seating load set to zero 3.5.2 B8, S6, X8, Y9, R5, U3, N5, C2

-

Penetration rate 3.5.3 - -

Test data 3.5.4 - -

Accuracy of graph 3.5.5 Not in test method Majority of participants

Zero-point correction 3.5.6 D8, U9, K8, F2, J7, T2, W8, V5

-

Rounding 3.5.7

C6, C8, J6, B8, S6, X8, S7, D3, G4, C2, E4, R6, X7, G2, R7

-

Pre-compaction curing 3.6.1 - Z6, S6, X8, X6

CBR compaction 3.6.2 N4, T8, E5, X7 W8, S7, D8, C6, K8, J6, F2, X6, J8, N3, N9, X3, K4, M3

OMC & MDD 3.6.3 - -

LDR & LMR 3.6.4 P7, W8, X8, Y3, G2, Q7, X3

-

Inconsistent results and calculations

3.6.4

C8, X8, U3, D3, N4, T8, P7, W8, V3, Z3, Y3, Q7

-

Table 2.2A – Participants identified where investigation or review follow up is warranted.



To the many out there “well done” and “thank you” for your participation.

The CV over this time has been around 30 % whereas this program has a CV of 21%. Note that the ‘gold’ highlighting shows programs conducted to the current 2014 test method. It shows that the spread (variation) in CBR test results are heading in the right direction.

Year Program Median CV

2016 67 155 21

2015 59 140 20

2014 54 74 31

2013 46 37 29

2012 37 44 20

2011 48 61 35

2009 16 30 32

Table 2.3A Comparison of CBR program results for the last seven years

Why is the middle 50% important? At present the spread of results is extremely large and affects the repeatability and reproducibility of the test. In other words, if it is too large the CBR results become meaningless. Based on this national proficiency program and others the CBR results appear of limited value to the end user. However, if put in context as to where the CBR results are used the situation may not be so bad. On a regional basis, where the CBR results are used, there may be much closer agreement. This may be due to similar training or better overseeing by a technical body etc. (e.g. Road Authorities) Has the CBR test results always been subject to the same large spread in results? Most likely it has. It may have been that it just was either not observed due to no national PT programs or seemed unimportant at the time. There is nothing in the test method that has changed substantially over the years to cause a change in the spread of results obtained. Staff are no better or worse trained then previously. What has changed over the last 50 years however is how results are interpreted and used. Road Authorities did much of the road construction work and testing so CBR results were basically in-house. Results were generally compared amongst those trained the same way using similar or same equipment. There was not the proliferation of small testing laboratories back then or the need to compare results from one State to another. National CBR proficiency programs for CBR were either not run or if so very infrequent. Today there are laboratories with quite diverse views on the CBR method and using quite different equipment. The test method allows considerable latitude in the performance of the test. It is not unexpected that the variation across Australia is as large as it is.



How can improving the accuracy help. It was hoped that improving the accuracy of testing would significantly reduce the spread in results shown. This program has shown that this may not be the case. The accuracy of many of the test results was shown that they could be improved but it did not necessarily lead to a significant reduction in the spread of the middle 50% of participants. Accuracy of testing still needs to be improved and most laboratories are trying to do this. Graphing has a significant impact on the overall accuracy achieved. Section 3.5 focus on those aspects most directly affecting CBR accuracy. What aspects of the test affect the outcome indirectly? The test method puts limits on the indirect aspects of the test such as moisture, compaction, LDR and LMR etc. It would appear at present, that while these are important, the control of them and how it affects the outcome is difficult to predict or quantify. Most cannot be examined in isolation nor is it clear how they interact. See section 3.6. Removing those results that did not comply with the limits placed by the test method did not, in this program, lead to an improvement in the spread of results. Can changes to the test method help? The last change to the test method has seen a significant reduction to the spread of results obtained. Based on the technical comments (section 3.7) it appears that while incremental improvements are possible any major improvement may need a substantial rethink of the test method. How can laboratories improve? Proficiency testing programs that provide technical feedback assist laboratories to improve. All of the technical comment detailed in section 3 has this in mind and is aimed at helping laboratories to have a greater understanding of the test. 2.4 Program Summary There has been an observable improvement in CBR testing over the last six years as measured by the coefficient of variation (CV). Previous proficiency programs have highlighted the need to reduce the variation shown by the middle 50 % of participants. The technical comment indicates that there are ways to reduce this slightly but it may be that this spread is just reflecting the accuracy of this test. The program shows that there are several improvements that laboratories can make to improve the accuracy of their individual results. It is highly desirable as it will overall reduce the spread of results. Improvements in repeatability are also needed. Improvements in accuracy however may not directly transfer to a significant reduction in the spread in results.



The program identified those aspects of the test that most affect accuracy (direct influences) and those aspects of the test that have less influence (indirect). There are aspects of the test method such as graphing and zero correction where further guidance is needed for the industry. The CBR graph is the only way of checking the validity of the results obtained. In most cases the graphs prepared do not adequately address this issue. Both these and other issues are identified as major contributors to CBR accuracy. The program showed that penetration rates may contribution significantly to the spread in results. Many participants were identified (>65%) as needing to review one or more aspects of testing. Therefore, test results for all sixty-five participants were recalculated based on the test data submitted. This allowed several conclusions to be drawn that previously had not been able to be answered in past programs. What this means is that every participant should review the testing submitted against the technical comments made in this report. Improvements to the test method, by better defining the test process, limits and expected outcomes would significantly improve the accuracy of the test. The statistics used in all proficiency programs is there for guidance. Care however needs to be exercised to avoid incorrect conclusions being drawn. This is one of the reasons that LabSmart Services provides comprehensive technical comment for each program. This proficiency program provides increased understanding of current test practices and potential sources of variation. It also allows monitoring of improvements in testing and provides the opportunity for participants to improve their competency. A summary of the program statistics is shown in Table 2.4A.

Statistic CBR A CBR B

Number of participants 61 63

Median 155 168

Normalized IQR 32 35

Minimum* 81 88

Maximum* 222 258

Range* 141 170

CV (%) 21 21

Table 2.4A Summary of statistics for the CBR program. Some results have been rounded. *Min, Max & Range

are with outliers excluded.



The observed variation (based on CV) has improved compared to other proficiency programs conducted over the last decade.

3.0 Technical comment The feedback is extremely lengthy and for this we apologise. It is unlikely that such detailed feedback will be offered in the future. In today’s vernacular, it is a “conversation” that the industry needs to have. It is hoped that this report will contribute to that discussion. 3.1 General performance Proficiency program participants are expected to comply with the requirements of the program and meet basic laboratory standards. General performance covers those aspects of laboratory operations that are expected to be performed as part of good laboratory practice and in keeping with NATA accreditation. Some aspects that are particularly relevant for this program are:

Supervision of testing

Following the test method

Following proficiency testing instructions

Correctly filling out paperwork i.e. PT log sheet

Checking of results

Free of errors i.e. calculations correct

Reality check of results i.e. does it fit the type of material submitted

Compared to earlier CBR proficiency testing programs there has been significant improvement in most of the above areas. However as detailed in subsequent sections there is still a considerable way to go to improve the accuracy of testing. It raises the question that if participants are not meeting the above basic requirements then what other omissions or errors are occurring during testing that remain undetected. 3.1.1 Supply of program information

Several participants supplied all the testing details requested. This information is used

to provide the feedback given in the following sections and is an important part of the

program.

Participants are always welcome to contact the program coordinator if they require

further explanation as to what information is required or how to proceed.

The information requested is also used to validate the results obtained.



Proficiency testing program providers may reject results on this basis if they do not

conform to the program requirements.

3.1.2 Errors

Errors may arise from several sources, an incorrect calculation, transcription error, wrong methodology used, not following the test method etc. Many of the comments in the following sections relate to errors. For example, participant 5-U9-A load /penetration results may have been entered the wrong way around on the log sheet. Or it could be that the CBR values are the wrong way around. Either way it corrupts the statistics used to assess the program outcome as well as being incorrect. Although some of these may have only a small impact they do accumulate and should not occur. Others can have a large impact such as incorrect graphing technique and zero correction.

Reduction in the number of errors detected in this program would significantly improve

the credibility of CBR testing and possibly reduce the variation (spread) in CBR results

obtained.

3.2 Statistical reality

The use of statistics are a very useful and practical means of analysing test data.

Those that use statistics everyday know the limitations and shortcomings of their use.

Unfortunately, they often do not get aired sufficiently to remind those who only

occasionally use statistics. This section addresses some of these aspects associated

with this report.

3.2.1 Accuracy of data

If the test data is in error, then any statistics calculated may also be error. Any

interpretations made, based on the statistics, may also be in error. Most proficiency

programs can handle a few inaccurate results without any concern about the validity

(accuracy and precision of the outcome) of the program. Most of the technical

comment concerns the accuracy of the CBR test results. The number of results that

are questionable does raise significant concern about the validity of many of the test

results.

3.2.2 Variation in CBR results

Often proficiency testing programs tend to focus on feedback concerning those with results that seem either too high or too low (outliers). While this is important sometimes other areas become just as important. The fundamental issue with CBR test results is that there is too large a spread shown by the middle 50% of participants. Within this group the results are too spread out.



This means that identifying accurately a median value or outliers may be seriously compromised. It seriously affects the accuracy and precision of the test results. Without improvement or better understanding of CBR test results there is a strong risk

that the test may no longer be credible.

3.2.3 “Set s.d limit”

In previous CBR proficiency programs the z-score statistics have been recalculated

using a “Set s.d limit” or “Target s.d”. The purpose of which was to bring the variation

(spread) in results back to something useful to geotechnical engineers and other

clients. It is a very practical way of approaching the problem. There is no reason to

suspect that, based on the outcome of this program, any result within the middle 50%

is better than another result from the middle 50%. The “Set s.d limit” outcome then

does not give much useful information other than an exercise in setting a limit. It

becomes a bit of a ‘Round peg in a square hole’ approach.

If the accuracy of most test results is questionable along with the median value, then

results may lie above or below the set limits. It does not identify problems or inaccurate

results, worse, it will indicate results as being satisfactory when they are not.

It has still been used in this program mainly as an indicator as to where a reasonable

variation limit may lie. So long as it is not taken that anyone test result is more accurate

them another then it is reasonable to use this approach.

In previous CBR proficiency programs LabSmart Services has given some guidance

as to what could be used as an acceptable spread from an “End User” perspective. A

variation considered reasonable has been based on ± 9.5 % (coefficient of variation)

of the median. Calculated target values are shown in table 3.2.3A below for this

program. Results as submitted have been used.

See Section 4.4

Median CV (%) S.D. Limit

Sample A 155.2 % 9.5 ± 14.75 %

Sample B 167.8 % 9.5 ± 15.94 %

Table 3.2.3A Target S.D Limits. Bearing Ratio at 5.0 mm

Please note that the following “Set s.d limit” outcomes do not constitute an

outlier in this program but provide one approach to determining which participant

results may be improved on further review.



Results were recalculated using the above ‘Set SD Limits’ as detailed in section 4.4

Based on these limits, participants exhibiting statistically significant variation are

shown in table 3.2.3B below.

Sample A - Review Sample B - Review

Z-score> 3 Z-score> 2.75 Z-score> 3 Z-score> 2.75

M8, U9, F2, X5, U7, B8, T2, U3, S7, T5,

N3, Z3, Y3, V5 K8

L8, J6, J7, T2, R5, N8, S7, K2, N3, P6,

Y3, V5 U7

Table 3.2.3B Statistically significant unrounded CBR results based on a set “SD Limit”.

Participants shown above may find it beneficial to review the performance of this test.

Also as all the CBR results shown in table 3.2.3B are very large from an engineering

perspective these may still be considered acceptable depending on the use of the

material.

3.2.4 Repeatability

If the spread of results both within and between participants is large it is hard to arrive

at a sensible repeatability and reproducibility outcomes. The accuracy of the results

also has a large impact. See section 3.3.4 for more detail on repeatability. Hopefully

future programs may result in better estimates of repeatability.

3.3 CBR Results

3.3.1 Participant assessment

Participant performance has been assessed in three ways:

Z-scores based on submitted CBR results (statistical outliers)

Identification of inconsistences, non-adherence to test method and errors

Accuracy of calculations

Repeatability

Participants need to be aware that the program coordinator performing the checks

may not have access to the full set of results for each participant. Also, due to the

large amount of data associated with this program it is entirely possible that the

coordinator may not have recalculated some participants results correctly.

Participants are asked to “investigate” matters that are statistical outliers and where

the test method has not been followed or are outside the limits set in the test method.



Other maters identified are shown as “Review”. These are matters that would help

improve testing and it most cases would be considered outside normal testing

parameters. It is sometimes difficult to determine as the test method often does not

provide sufficient guidance.

As an aid to identifying usable limits “Set sd limits’ have been calculated but do not

form part of the assessment.

3.3.2 CBR results

Z-scores and associated statistics were calculated on the CBR results as submitted

and are detailed in section 4.1. The following statistical outliers were identified:

Sample A Sample B

Investigate Review Investigate Review

V5 - S7 -

Table 3.3.2A Participants identified as having statistical outliers in the program

For the CBR test the spread of results is very large over the middle 50% of participants.

Both sample A and B were the same material. The repeatability outcome was

statistically good but the accuracy of the data called the outcome into question (see

section 3.3.4 for more detail).

It makes it extremely difficult to draw accurate conclusions from the statistics. For

example, participant V5 had a high CBR result and was identified as an outlier for

sample A. However participant V5 had an even larger CBR result for sample B but it

was not identified as an outlier! The statistics are correct it is just a reflection of very

poor reproducibility and repeatability.

The construction industry may need to acknowledge, if improvement cannot be

established, that this is the accuracy and precision of the CBR test.

Sections 3.5, 3.6 and 3.7 explores this further.

3.3.3 Identification of inconsistences and errors

There are many steps within the conduct of the test (methodology) that can become a

source of error or where inconsistencies can occur. As well there are limits posed by

the test method itself that may also contribute. For example, compaction and moisture

content.



To better understand the influence that these sources have on the variation of the test

they have been broken up into those that directly affect the CBR result and can be

measured and those where the impact on the CBR result cannot be easily measured

i.e. indirect. See section 3.4 for more information on determining direct and indirect

influences.

Direct influences generally involve participant errors in testing. These are discussed

in more detail in section 3.5.

The following calculation was used to determine if a submitted result required further

appraisal.

[ ( Load5.0 - Load2.5 )*100 ] / 2.5 where Load is in kN.

This could also be used by supervisors as a quick means of checking test data as it

does not need the graph.

This check was undertaken. As it showed a large number to check it was decided in

the end to recalculate everyone’s results. The outcome of this exercise is shown in

section 4.2.

The recalculated results have been used to determine performance in many instances.

This gave a more accurate appraisal and did not change the outlier outcome except

to show a better performance for some individuals.

Indirect influences generally involve non – compliance to the test method requirements

or limits. These are discussed in section 3.6.

3.3.4 Repeatability

The spread of results was much larger in earlier programs. Previously it was felt that

investigating methodology yielded better information then duplicate samples would

have. The test method was revised in 2014 and addressed some shortcomings in

relation to the compaction process. This led to changes in methodology for some

laboratories and improvement in the CBR variation i.e. CBR Proficiency Program

2015(59) CV was 20%.

The new test method has now had a reasonable period to ‘bed in’. As consequence

if was felt that it was appropriate to use duplicate samples for this program to measure

repeatability.

Unfortunately, the large spread in results obtained affects the repeatability outcome.

The number of participants where the CBR value calculated by participants was shown

to be inaccurate was quite high. Considering both these factors makes the estimate

of repeatability shaky. Z-score statistics are shown in section 4.3



An alternative approach would be to use the homogeneity data as an estimate.

However, this may also be a shaky estimate. The precision may be good (same

machine and pace rate) but the accuracy may be poor.

The repeatability was calculated (sample A and B combined) with the participants

results (section 3.3.2) as submitted and as corrected (section 3.3.3). Only the original

participant’s results are shown in section 4.3, repeatability for the recalculated results

has been omitted from the report (to reduce the report volume).

By using the recalculated CBR results it reduces the number of participants shown as

needing to either investigate or review their outcomes, table 3.3.4A.

Based on submitted CBRs Based on recalculated CBRs

Between laboratories Within laboratory Between laboratories Within laboratory

Investigate Review Investigate Review Investigate Review Investigate Review

V5 S7 F2, U7,

R5 X3 - -

U7, S7, X3

-

Table 3.3.4A Repeatability statistics summary for submitted results and recalculated

3.4 Measurement Uncertainty (1)

The intention is not to calculate MU for the CBR test. It is however necessary to

identify components that contribute to the MU broadly to better understand what

contributes and what can be controlled in regards to the spread of CBR results.

It is helpful to review a simple case first involving moisture content (MC). A simplified

MC calculation follows:

MC = (wet mass - dry mass) / dry mass X 100

The ‘100’, is used to convert to a percentage, it is a constant (i.e. does not change)

and has no uncertainty attributed to it.

The mass readings are principally affected by the uncertainty associated with the

balance used. Other smaller uncertainties associated with the measurements, such

as drying to constant mass, can be ignored in this instance.

The important feature to note is that each measurement (of mass) has an uncertainty

assigned that directly influences the overall moisture content result (MC) and the

uncertainty obtained.



Note (1): In this section the intention is to convey the different ways a MU budget is considered. The

information detailed is a generalisation and a simplification. MU terminology and jargon has been kept

to a minimum as well as explanations to convey the general concept. The concept “direct” and “indirect”

are not normally used in MU but are introduced here as a means of demonstrating a concept.

CBR – MU involving - Direct Influences

The bearing ratio (BR) calculation can be expressed as:

BR = Load(@5mm) / 19.8 X 100

As with MC both “19.8” and “100 “are constants and have no uncertainty attributed to

them. There are several uncertainties that can be directly related to or directly

influence the “Load” measurement:

Accuracy of the load cell

Accuracy of seating load

Accuracy of penetration

Accuracy of the rate of penetration

Accuracy of recording force readings

Number of data points selected

Accuracy of the graph prepared

Accuracy of the zero correction

Rounding of results

The magnitude of these influences on a load can usually be directly measured or

calculated.

CBR – MU involving - Indirect Influences

The MU calculation involving ‘indirect influences’ is usually added to the formula, as

shown in ‘gold’.

MUBR = [ Load(@5mm) ± MUDI / 19.8 X 100 ] ± MUA ± MUB ± MUC etc.

The effect of indirect influences on the BR MU calculated normally cannot be

measured or directly calculated. Generally indirect influences are estimated or

determined experimentally.

To either estimate or determine experimentally usually requires that each influence

can be separated. For the CBR test it is neither practical (very costly) or possible in

most instances to do this. Indirect uncertainties for the BR relate to the determination

of:

OMC & MDD

Moisture content

LDR & LMR

And the associated effect on MU of:



Curing of sample

Compaction i.e. layer thickness, compaction pattern, number of blows, achievement of

LDR & LMR

Soil characteristics

A further difficulty in determining or isolating these indirect influences is that they can

interact with each other in unknown ways. For example, how a low MC with excessive

number of compaction blows affects the BR measurement is impractical to determine.

Another difficulty is that many of these measurements are subject to a natural variation

as well from one participant to another, compounding the problem of performing any

realistic comparison.

3.5 Direct Influences

The following sections cover many aspects of methodology. Of note is that even with

corrections resulting from re-graphed data and using unrounded results if has only a

marginal effect on the middle 50% of participants. In other words, the corrections are

totally random with some corrected CBR values increasing while others decrease.

See table below of relevant statistics taken from section 4.2.

Sample A Sample A

Submitted Recalculated Submitted Recalculated

Median 157.4 159.4 168.9 170.6

Third Quartile

136.6 138.0 150.0 151.2

First Quartile

180.2 176.7 197.5 199.3

IQR 43.6 38.7 47.5 48.1

N-IQR 32.3 28.7 35.2 35.7

Minimum 81.0 96.8 60.0 63.7

Maximum 252.4 222.7 258.1 232.8

Range 171.4 125.9 198.1 169.1

CV (%) 20.5 18.0 20.8 20.9

Table 3.5A Summary of statistics for ‘direct influences’ for both submitted and recalculated results

Overall it suggests that while the accuracy of testing can and should be improved there

may be little change to the overall spread of results obtained for the CBR test.

3.5.1 Load cell

In section 6 the load values are shown for each participant. In some cases, there is a

NR (not reported) for some penetrations. It should be noted that this may be due to

the upper limit of the load cell having been reached. It may also be due to values not

corresponding exactly to the penetrations requested. Some laboratories used more



data points than requested (great to see) but have not been included in the tabulated

results.

Most participants in this program used load cells with seven participants (S6, N5, C4,

Y3, V5, C2 & M3) using load rings. Most were calibrated to ‘Class ‘A’ or a combination

e.g. A/B/C. Most participants used a 50kN load device with the highest being 200kN.

Participants should be aware that as the cell range increases the accuracy will

decrease in many cases.

Selection of the correct load cell capacity is dependent on the experience of the

laboratory and where possible prior knowledge the of the material to be tested.

Unfortunately, due to the large range of results possible, warning cannot be given by

the program organisers prior to testing. Several participants exceed the capacity of

the load cell during testing. It is important that testing be stopped on approach to the

capacity of the load cell. Some participants exceed the maximum capacity of their cell

by a considerable amount (Z6, W8, J7, X6, Z3, Y3 & M3). This can cause permanent

damage particularly if it is a load ring.

Participants (L6, T5, V3, M7, E9 & L7) used a 25kN cell (Max CBR 120%) and found

that the CBR value was outside this range. Some reported the result while others

reported, correctly, no result. These have been corrected in the CBR data analysis.

Another consideration is the resolution at the lower end of the load scale to accurately

measure the seating load. For load cells used in this program that are on the larger

side (e.g. 50kN) it may be difficult to accurately measure small loads.

Often this is not a lack in ability of the load cell but a reflection of the normal calibration

practise where the calibration may not extend to the low load values required for

seating loads. Laboratories may need to request calibration facilities, where possible,

to specifically cover the seating loads required when undertaking the load cell

calibration.

3.5.2 Seating load

The standard requires that the least amount of force be used for the seating load. It

is important that the piston is in contact with a stable surface. The seating load is

considered the ‘zero point’ from which the load values and penetration commence.

In past programs participants had difficulty in determining the correct seating load to

use. For this program the instructions indicated that the CBR would be greater than

30% and, as specified in the test method, a seating load of 250 kN should have been

used.

The following participants did not follow the test method or program instructions and

incorrectly used a seating load of less than 50N.



M8, D8, U9, T9, L8, Z6, F2, W8, J7, B8, S6, T2, Y9, A2, X6, R5, N8, U3, S7, M4, U3,

E9, J8, A3, K2, N3, L7, N9, X3, N5, Z3, P6, C4, Y3, Q5, C2, E4, M3, R6, G2 and R7

At high CBRs the seating load has only minimal effect on the CBR obtained but does

influence where the penetration points fall. For this type of material any effect of

incorrect assignment of the zero penetration is usually cancelled out with the zero-

point correction offset if performed correctly.

Setting the seating load to zero was done by most participants except (B8, S6, X8,

Y9, R5, U3, N5, C2). Not setting ‘back to zero’ again can lead to an inaccuracy in the

load scale creating an offset.

However, errors in both processes (seating load applied and resetting back to zero)

may influence the CBR result by up to ± 1.3% CBR. This may not seem much but in

the rounding process when reporting this may cause a difference of 10%.

3.5.3 Penetration rate

Test method indicates that the machine used must be capable of “….forcing the

penetration piston into the specimen at uniform (not pulsating) rate of 1.0± 0.2 mm/min

during the complete test….”. The penetration rate had in the past not been routinely

checked until NATA in recent years required it be checked every two years.

It is not entirely clear, based on input from participants, if the standard means an

‘average rate’ of if it means it must be met at ‘all times’. If it is taken as an average

rate then theoretically you could have half the penetration at 0.5 mm/min and the other

half at 1.5 mm/min and still arrive at the average rate of 1.0 mm/min.

For ‘hand’ operated devices it is hard to check other than an overall average. A

motorised platform was used by the majority of participants with seven participants

(K8, L5, U3, N3, Q5, K4, V5) using a hand operated unit.

With load cell units, they usually allow the rate to be checked as you go on a ‘per 0.5

mm of travel’ etc. This can be done on a ‘test by test’ basis so is a very good record

of meeting the requirements of the standard.

Participant J8 reported the penetration rates as detailed in table 3.5.3A. The average

value obtained of 0.84 mm/min meets the test method requirements. All participants

reported a penetration rate within the Australian Standard specified range of 1.0 ± 0.2

mm/min.

Very few reported penetration rates to this accuracy most participants appear to have

quoted just the test method requirements (i.e.1 mm/min) rather than stating a

calculated or measured average penetration rate. The test method does not ask that

this be done. It raises however the question as to whether most participants had

something different, more in keeping with what is shown in the table 3.5.3A.



A load cell or ring may compress around 0.4 mm under high loads which contributes

to the penetration rate achieved. In future, the NATA ‘penetration checks’ may need

to be requested.

Penetration Penetration Rate

mm mm/min

0.50 0.69

1.00 0.86

1.50 0.82

2.00 0.79

2.50 0.78

3.00 0.79

3.50 0.80

4.00 0.80

4.50 0.87

5.00 0.91

5.50 0.88

6.00 0.87

6.50 0.89

7.00 0.95

7.50 0.95

Average = 0.84

Table 3.5.3A Penetration rates for participant J8

The penetration rate is linked to the slope of the force/penetration curve. It is therefore

significant in determining the CBR and hence the set limits placed on the rate of travel

by the test method.

Graph 3.5.3B Effect of applying the tolerance on the penetration rate 1.0 ± 0.2 mm/min

0

5

10

15

20

25

30

35

40

0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0

Load

Penetration

Penetration at 4.8, 5.0 and 5.2 mm for CBR 160

1.2 mm/min 1.0 mm/min

0.8 mm/min



The rate can be interpreted in terms of time or penetration. If it takes 5 minutes to

penetrate 5 mm. It takes 6.25 minutes to penetrate 5 mm at a rate of 0.8 mm/min and

4.17 minutes to penetrate 5 mm at a rate of 1.2 mm/min. Alternatively, it can be viewed

as the load at 4.8, 5.0 and 5.2 mm as shown in graph 3.5.3B.

Regardless of the approach the outcome remains the same, for 5 mm penetration the

accuracy is therefore ± 0.2 mm. For a CBR of 162% this translates into approximately

± 6.6%. This is detailed in table 3.5.3C.

Penetration mm

Load kN

CBR %

Difference CBR %

CV %

4.8 30.7 155.0 -6.6 -4.1

5.0 32.0 161.6 0.0 -

5.2 33.3 168.2 6.6 4.1

Table 3.5.3C Variation in CBR for rate of 1.0 ± 0.2 mm/min.

For this program where the CV was 21 % a possible ± 4 % CV is significant. Improving

the accuracy of penetration would also reduce the spread of results obtained. Even

at lower CBR values the CV variation remains significant.

There is an assumption that the slope associated with penetration remains constant

regardless of the rate of penetration. This means that the soil offers the same

resistance no matter how quick or slow you push.

It is possible that for some soils pushing slowly may allow the soil to “move out of the

way” easier than if pushed faster against the soil. The stresses in the soil may be

different. The effect cannot be easily calculated. Some experimentation would be

needed to determine if there is a significant effect or not.

3.5.4 Test (penetration / load) data

The number of penetration points selected is extremely important. Many

laboratories recorded the requested additional load/penetration data. A few took less

than that requested for this proficiency program or terminated the test before 12.5 mm.

The test method specifies a minimum data set (0.5, 1.0, 1.5, 2.0, 2.5, 3.0, 4.0, 5.0, 7.5,

10.0 and 12.5 mm penetrations).

The key word in the test method is “at least”. In other words if you know the material

well (i.e. have a CBR history of the material) then you should be able to use fewer

points otherwise you need to record loads at more points.



Additional points are needed to:

Allow for the discount of an abnormal data value Have sufficient points left so that the discounting of a point does not

compromise the test result Have sufficient points to fit a straight line and a curve Have sufficient points above the straight section of the graph. Have sufficient points to be able to tell that you have an abnormal data point

Participant E5 was selected but there were many other participants with small data

sets. The penetration/load values submitted for participant E5 were used to produce

a graph and a zero-correction line. The results are shown below Graph 3.5.4A.

3.5.4A Load / penetration graph for participant E5, Sample B

Only the minimum data points have been collected. The graph shows that there was

one data point only between 5 mm and 10 mm (i.e. circled data in the graph above).

If the data point at 7.5 is out it can have a large effect on the CBR obtained. If more

points had been taken, then the uncertainty about this point would be removed.

It is evident that two few data points can have a measurable difference on the result

that is obtained. Greater confidence in the result and accuracy is obtained when more

points are taken.

3.5.5 Accuracy of the graph prepared

Graphing has been singled out due to its importance in deriving an accurate result and

being able to check the CBR result obtained. The CBR test method does not emphasis

this aspect.

y = 9.7868x4 - 255.62x3 + 2104.1x2 - 772.55x + 74.034R² = 1

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

50,000

0 1 2 3 4 5 6 7 8 9 10 11 12

Ap

plie

d L

oad

(N

)

Penetration (mm)

CBR Graph for Participant 66 - E5 - B

Data Values

Poly. (Data Values)

Correction



Graphing of results has been an issue for the last seven CBR proficiency programs (7

years). Overall graphing has improved vastly over this time but there is still

considerable room for improvement.

In nearly every case you can take the raw data from a AS 1289 test method and

everyone would calculate the same result. With CBR the raw data can be given to 12

or more laboratories and possibly get 12 different answers!

From a testing perspective, this is unacceptable but within the test method. This

is not the fault of laboratories but it is within their scope and ability to improve on

this.

Regardless of what graph is submitted to the client a detailed graph for use by the

laboratory is important as it is the primary method of checking that a reasonable

result has been obtained.

This is also how the program coordinator checked if participant’s results matched the

data submitted. Unfortunately, this is not conveyed by the test method. The test

method is also not very descriptive regarding the quality of the graph prepared.

In previous proficiency programs, considerable feedback has been given. An example

graph is given in Appendix C. This is the level of detail and quality that laboratories

should be aiming.

Participants are welcome to contact LabSmart Services and request a copy of the

recalculated graph.

The following sections expand on issues where better graphing practice would have

improved the accuracy of the result obtained.

3.5.6 Zero-point correction

Overall, most participants correctly calculated the zero-point correction and applied it. Seating load and zero correction combined generally result in small changes.

However sometimes small changes can have a significant effect and particularly when

a BR value is to be rounded either up or down to the nearest 10%. A variation of ±

20 % CBR is not unrealistic.

Not applying the zero-point correction does have a significant impact. For example,

participant (J7) did not correct the raw data back to a zero point. Participant (V5)

appears to have overestimated the correction needed.

Participants J7 and V5 data have been re-graphed (3.5.6A & B) and the bearing ratio

at 5 mm recalculated.



3.5.6A Load / penetration graph for participant J7, Sample B

3.5.6B Load / penetration graph for participant V5, Sample A

y = 10.693x4 - 269x3 + 2270.2x2 - 1264.1x + 163.58R² = 0.9999

0

4,000

8,000

12,000

16,000

20,000

24,000

28,000

32,000

36,000

40,000

44,000

48,000

52,000

56,000

0 1 2 3 4 5 6 7 8 9 10 11 12

Ap

plie

d L

oad

(N

)

Penetration (mm)

CBR Graph for Participant 21 - J7 - B

Data Values

Poly. (Data Values)

Correction

y = 110.5x4 - 1331.7x3 + 5375.9x2 + 114.05x + 202.35R² = 0.9973

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

45,000

50,000

0 1 2 3 4 5 6 7 8

Ap

plie

d L

oad

(N

)

Penetration (mm)

CBR Graph for Participant 59 - V5 - A

Data Values

Poly. (Data Values)

Correction



Table 3.5.6C Submitted and recalculated results for CBR and zero-correction for participant J7

Similarly, for participant V5.

Table 3.5.6D Submitted and recalculated results for CBR and zero-correction for participant V5

The CBR graphs for all participants were re-graphed. Although every effort was made

to make these as correct as possible they could only be reproduced with the data

provided. See section 4.2.

For this program the difference between the submitted value and the recalculated

value was considered significant if the difference was 0.5 mm or greater. These

participants are shown in table 3.5.6E.

Difference in zero-correction greater than 0.5 mm

Investigate

Sample A Sample B

D8, U9, K8, F2, J7, T2, V5 K8, F2, W8, V5

3.5.4E Participants where the zero- correction is greater than 0.5 mm

It highlights the need for the middle group of participants to review their results

as much as those at the upper and lower edges. Overall every participant should

revisit the graphing technique employed.

3.5.7 Rounding of CBR

The reason for rounding is not entirely clear in the Australian Standard. It perhaps

acknowledges that CBR values are quite variable and rounding makes the results

Participant J7 – B Submitted Values Recalculated values Difference

Zero correction (mm) 0 1.3 1.3

Unrounded CBR (%) 119 162 43

Participant V5 - A Submitted Values Recalculated values Difference

Zero correction (mm) 1.3 0.4 -0.9

Unrounded CBR (%) 252 213 -39



easier to use and compare when grouped together i.e. takes out some of the

fluctuation.

Laboratories were asked for the unrounded Bearing Ratio rather than rounded CBR

results. Part of the design consideration of this program was to try and isolate as well

as minimise sources of variation. The process of ‘rounding’ was identified as adding

to the variation of determining CBR. The statistics associated and test variation with

the CBR results will increase slightly if rounded results are used. This is demonstrated

in the summary of the statistics detailed in table 3.5.7A.

Several participants supplied rounded results (C6, C8, J6, B8, S6, X8, S7, D3, G4,

C2, E4, R6, X7, G2, R7). Unrounded was required by the program due to the impact

on the statistics generated. These participants need to investigate the reason for

rounding the results.

Sample A Sample B

Unrounded Rounded Unrounded Rounded

Number 61 60 63 60

Median 155.2 160 167.8 165

N-IQR 32.3 29.7 34.8 38.9

Minimum 81.0 80 60.0 60

Maximum 252.4 250 258.1 230

Range 171.4 170 198.1 170

CV (%) 20.8 18.5 20.8 23.6

Table 3.5.7A Effect on statistics for rounded and unrounded CBR results

3.6 Indirect Influences

As mentioned previously the following aspects of testing methodology are difficult to

relate to the final CBR test result. They can be measured individually but the influence

it has on the CBR result is more difficult due to the ‘unknown interactions’ they have

on each other.

Section 4.2 identifies, by colour coding, the ‘indirect influences’ that are discussed in

this section (i.e. compaction blows, LMC, LDR etc.). Results have been flagged that

show a significant departure from the test method. If these were to be deleted and

those left (not many) are analysed statistically the variation (spread) in results remains

much the same.



Sample A Sample B

Submitted Less indirect Submitted Less indirect

Number 60 43 62 42

Median 157.4 161.7 168.9 163.9

Third Quartile 136.6 137.2 150.0 153.6

First Quartile 180.2 179.3 197.5 192.7

IQR 43.6 42.2 47.5 39.0

N-IQR 32.3 31.2 35.2 28.9

Minimum 81.0 100.6 60.0 108.5

Maximum 252.4 222.7 258.1 232.8

Range 171.4 122.1 198.1 124.3

CV (%) 20.5 19.3 20.8 17.7

Table 3.6 Effect on statistics for submitted CBR results and those less indirect

There is some change to the overall spread of results by deleting suspect results but

by no means large, due to the accuracy of results themselves, making the outcome

less assured.

It is clear however that more accurate measurement of these aspects of the test in

conjunction with better definition within the test method would assist with improving

the overall accuracy of the test.

3.6.1 Pre-compaction curing

There were a range of curing times used by participants. The majority used 48 hours and above. The curing times specified by the test method are minimums. More curing is better than less.

Participants (Z6, S6, X8, X6) used curing times of less than 24 hours. These curing

times are at odds with the rest of the participants and should be reviewed.

The process to be used when curing material does not appear to be documented.

Thus, there is a strong probability that many laboratories use quite different

approaches, some being more effective than others.

Samples need to be in sealed containers and the material broken up and mixed

regularly during curing. Water should be added as a mist to the largest surface area

possible. Condensation on the container side and lid needs to be monitored. Regular

mixing should avoid material on the bottom being wetter than the rest of the material.

3.6.2 CBR compaction

The proficiency program required participants to perform the CBR compaction using the OMC and MDD values provided and 100 % standard compaction.



Test methods relating to compaction are very specific about the energy input into the process. This is largely governed by the spread of hammer blows and the number of blows used. The revised CBR method now stipulates the pattern to be used when compacting the CBR mould. The test method however does not specifically require the number of blows delivered to be recorded. As it is an important part of the test it should be recorded. It is expected that by compacting a calculated amount of material to a set height that the desired density will be achieved. The blows will vary depending on the material type and moisture. Depending on how this is done a variation in the number of blows per layer is the typical outcome. However, between layers these should remain reasonably close. For determination of OMC/MDD using standard compaction 25 blows per layer is used. To achieve the same energy input around 53 blows is required for the larger CBR mould. More or less blows than 53 may be needed for a variety of reasons.

Inaccuracy of the OMC and MDD initially

Blows not delivered in a regular pattern

Nature of the material may cause it to move around the mould excessively

Material added is higher or lower than the prescribed layer depth The blows delivered provides an insight into whether any of the above issues may have had an effect. Relying on the dry density calculated is useful but it is a calculated value and dependant largely on how representative and accurate was the moisture determination. How much variation is reasonable. This is at present unknown but for this program a variation of 40 to 60 has been used with a variation between layers of 5 blows. The following participants shown in table 3.6.2A do not meet this criterion. Most shown did so for both sample A and B except for those underlined.

Sample A Sample B

< 40 Blows per layer > 60 blows per layer < 40 Blows per layer > 60 blows per layer

W8, S7 D8, C6, K8, J6, F2,

X6, N3, N9, K4 W8, S7

D8, C6, K8, J6, F2, X6, J8, N3, N9, X3,

K4, M3

Table 3.6.2A Participants with high or low number of compaction blows.



The bulk of participants, outside the limits set, used more than 60 blows per layer. It may not affect the dry density obtained but there is concern that it may have an effect such as;

orienting the soil particles,

segregation of particles

causing fissures,

breaking up of particles

uneven compaction, all of which could influence the CBR without affecting the dry density value achieved. CBR results may be higher or lower depending on the influence. As far as is known these issues have not been investigated in recent times. There is also the possibility that these results do not belong to the general population of test results for this program. If a modified compaction hammer was used, then the number of blows needed for equivalent energy using 3 layers is approximately 20 blows. Two participants (N4, T8) used modified compaction over 3 layers (instead of 5). Two others (E5, X7) indicated standard compaction but used blows consistent with modified compaction. As the results, do not comply with the test method or proficiency testing program requirements the results obtained do not belong to the general population of test results. 3.6.3 OMC & MDD

Different determinations of OMC & MDD by different laboratories will give rise to a

spread of results (Variation). To limit the effect of this variation on the CBR testing in

this proficiency program the OMC & MDD have been predetermined. This information

was supplied to participants (See instructions Appendix A) so that all participants used

the same OMC & MDD values.

3.6.4 LDR and LMR

Calculation of LDR & LMR

Participants were requested to submit:

The sample moisture immediately prior to compaction (w1) in accordance with

clause 6(c) of the standard.

Moisture content variation (wv)

The Laboratory Moisture Ratio (LMR)

The Laboratory Density Ratio (LDR) and

Dry Density (before soaking)



These intermediate results are noted in the test method as needing to be reported or

required to determine compliance with the test method.

The reported LDR and LMR values were re-calculated using the reported moisture

from clause 6(c) and density (before soaking). It is suspected that several participants

had incorrectly reported the moisture of the sample as being that of ‘as received’.

There were several participants that had difficulty in calculating the intermediate

results detailed above. There were also many participants that did not report LNR &

LDR to the correct number of decimals or had rounded incorrectly.

The participants listed in Table 3.6.4A showed inconsistencies in the values submitted

throwing doubt on compliance with the test method and should be investigated.

Information submitted Investigate

Sample A B

Moisture (Clause 6c) X8, N4, T8 P7, N4, T8,

Variation in moisture content reported C8, X8, U3, D3, N4, T8 P7, Q7, C8, X8, U3, D3,

V3, N4, T8

LMR does not match reported moisture P7, W8, V3, Z3 W8, X8

LDR does not match reported dry density X8, Y3 Q7

Table 3.6.4A: Participants with inconsistencies in calculating LMR and LDR

Achievement of OMC & MDD

Participants were requested to compact the sample to 100 % standard compaction. A

few indicated that modified compaction was used (see section 3.6.2)

Overall most participants achieved the desired range for OMC and MDD which was a

very good outcome. Achieving the LMR and LDR is a requirement of the test method

and must be met for the results to be valid and hence reportable.



OMC

± 0.5%

Moisture

Range

%

LMR Range

%

Investigate

Sample A

Investigate

Sample B

P7, W8, X8, Y3, G2 P7, W8, X8, Y3. G2

8.1 94.2

8.6

9.1 105.8

MDD

t/m3

Density

Range

t/m3

LDR Range

± 1%

Investigate

Sample A

Investigate

Sample B

X8, X3, Y3 Q7, X8

2.237 99.0

2.260

2.283 101.0

Table 3.6.4B: Participants that are outside the limits set for LMR and LDR.

Participants with results outside these limits as detailed in Table 3.6.4B. It suspected

that in many cases LMR and LDR would have been achieved had the participant

calculated them correctly.

Results outside the permitted LMR and LDR ranges would normally be rejected from

the proficiency program. Participant codes shown in bold in table 3.6.4B may not meet

the test method requirements.

3.7 Test method

Often as part of a proficiency testing programs there is a need to discuss aspects of

the test that can be identified as contributing to the overall uncertainty of the test results

produced. It does not mean the test method needs to change only that it is important

for laboratories to know which aspects of the test, if not performed well, could add to

the variability of the outcome.

The need to change the method only arises if the accuracy and variability in the test

results is not within the expected range.



Aspects of the test that contribute to improving the accuracy and possibly reducing the

variability are:

Need for more sample, so test can be repeated if required

Standardised approach to curing – e.g. spray or mist, sealed container etc.

Better definition of graphing and curve fitting

Background on using graph to validate CBR result.

Use of more penetration points

Guidance on suspect data values

Better definition as to what is meant by penetration rate

Actual measured penetration rate per 1 mm to be recorded for each test

Recording the number of blows, i.e. energy input

Limits on number of blows per layer and between layers

Better definition of zero correction and line fitting

Test performed in duplicate with limit on repeatability

Need for more background guidance to reduce variability of opinion on how to perform test

Limit FSD of load cell/ring to CBR value obtained. I.e. not use a 100kN load cell for a CBR of 15.

Requirement to standardise the test using a known material that gives a CBR of 100%

Define acceptable repeatability and reproducibility for the test.

Use the average of two samples to report the average value. Results must be within repeatability value.



M8 205.5 1.56 T2 87.3 -2.10 X3 122.4 -1.01

D6 143.9 -0.35 Y9 140.5 -0.45 N5 173.0 0.55

D8 165.2 0.31 A2 146.0 -0.28 Z3 199.7 1.38

P7 154.6 -0.02 X6 159.6 0.14 P6 NR

U9 204.3 1.52 A7 191.9 1.14 C4 138.9 -0.50

C6 150 -0.16 R5 136.7 -0.57 Z9 NR

T9 171.7 0.51 N8 188.8 1.04 Y3 212.1 1.76

Q7 170.7 0.48 U3 218.6 1.96 Q5 135.2 -0.62

L8 115.2 -1.24 S7 100 -1.71 T7 NR

C8 140 -0.47 Q2 NR K4 162.3 0.22

Z6 171.1 0.49 M4 155.2 0.00 V5 252.4 3.01 #

K8 111.7 -1.35 D3 180 0.77 N4 126.1 -0.90

J6 180 0.77 G4 130.0 -0.78 T8 161.1 0.18

L5 167.8 0.39 U6 NR C2 180 0.77

F2 81.0 -2.30 T5 107.6 -1.47 E4 130 -0.78

X5 222.2 2.07 V3 125.8 -0.91 M3 180.8 0.79

D9 136.4 -0.58 M7 NR R6 150 -0.16

W8 189.9 1.07 E9 NR E5 189.9 1.07

U7 103.9 -1.59 J8 150.6 -0.14 X7 170 0.46

L6 NR A3 164 0.27 S4 NR

J7 152.0 -0.10 K2 181.7 0.82 G2 140.0 -0.47

B8 200 1.39 N3 216.7 1.90 R7 140.0 -0.47

S6 130 -0.78 L7 130.7 -0.76

X8 180 0.77 N9 145.5 -0.30

Number of results 61

Median 155.2

Median MU 5.2

First Quartile 136.4

Third Quartile 180.0

IQR 43.6

Normalised IQR 32.3

CV (%) 20.8

Minimum 81.0 (81.0)

Maximum 222.2 (252.4)

Range 141.2 (171.4)

4.1 Participant's CBR results - Sample A: Z - Scores

Statistic Value

Note: A # indicates an outlier where the z-score obtained is either greater then 3 or less than -

3. Codes for all participates are shown. The results column shows a blank entry for those

participants that did not submit a result for this test. Minimum, Maximum and Range are

calculated with outliers excluded, those in brackets include outliers.

Code

Test

Result

%

Z Score Code

Test

Result

%

Z ScoreCode

Test

Result

%

Z Score



57

68

59

16

32

46

55

1

5

22

51

29

18

66

31

45

64

13

24

36

62

50

7

11

8

67

14

3

44

58

61

28

ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.1 Participant's CBR results - Sample A: Z - Score Graph

V5X5U3N3Y3

M8U9B8Z3

A7W8E5N8

K2M3J6X8D3C2

N5T9Z6Q7X7L5D8A3K4T8X6M4

P7J7J8C6R6A2N9D6Y9C8G2R7C4R5D9Q5L7S6G4E4

N4V3X3

L8K8T5

U7S7

T2F2

-3 -2 -1 0 1 2 3



M8 195.2 0.79 T2 88.3 -2.28 X3 196.0 0.81

D6 129.1 -1.11 Y9 150.0 -0.51 N5 170.6 0.08

D8 208 1.15 A2 150.0 -0.51 Z3 186.4 0.53

P7 154.6 -0.38 X6 151.5 -0.47 P6 226.3 1.68

U9 157.4 -0.30 A7 202.0 0.98 C4 170.7 0.08

C6 140 -0.80 R5 229.7 1.78 Z9 NR

T9 171.8 0.11 N8 216.6 1.40 Y3 218.7 1.46

Q7 186.9 0.55 U3 190.1 0.64 Q5 143.8 -0.69

L8 112.0 -1.60 S7 60 -3.09 # T7 NR

C8 150 -0.51 Q2 NR K4 204.9 1.06

Z6 171.1 0.09 M4 167.8 0.00 V5 258.1 2.59

K8 131 -1.06 D3 120 -1.37 N4 157.9 -0.28

J6 220 1.50 G4 160.0 -0.22 T8 157.5 -0.30

L5 155.5 -0.35 U6 NR C2 170 0.06

F2 160.9 -0.20 T5 126.5 -1.19 E4 130 -1.08

X5 202.0 0.98 V3 126.1 -1.20 M3 198.0 0.87

D9 141.4 -0.76 M7 NR R6 160 -0.22

W8 210 1.21 E9 NR E5 151.5 -0.47

U7 213.3 1.31 J8 203.8 1.03 X7 180 0.35

L6 184.6 0.48 A3 188 0.58 S4 NR

J7 119.1 -1.40 K2 229.7 1.78 G2 140 -0.80

B8 180 0.35 N3 218.2 1.45 R7 160.0 -0.22

S6 130 -1.08 L7 160.0 -0.22

X8 150 -0.51 N9 176.2 0.24


Median 167.8

Median MU 5.5



IQR 47.0

Normalised IQR 34.8

CV (%) 20.8

Minimum 88.3 (60.0)

Maximum 258.1 (258.1)

Range 169.8 (198.1)

4.1 Participant's CBR results - Sample B: Z - Scores

Statistic Value





Code

Test

Result

%

Z Score Code

Test

Result

%

Z ScoreCode

Test

Result

%

Z Score



59

30

45

52

13

55

46

31

19

18

3

58

43

16

29

64

49

1

32

44

8

51

20

22

67

48

7

11

53

50

62

35

ReviewWeak

Consensus

Weak

ConsensusReview

Z-score

Strong Consensus

4.1 Participant's CBR results - Sample B: Z - Score Graph

V5R5K2P6

J6Y3N3N8U7W8D8K4J8X5A7

M3X3M8U3A3Q7Z3L6

B8X7N9T9Z6C4N5C2M4

F2G4L7R6R7N4T8U9L5P7X6E5C8X8Y9A2

Q5D9C6G2

K8S6E4D6T5V3

D3J7

L8T2

S7

-3 -2 -1 0 1 2 3



Zero

Correction

Revised

CorrectionDifference CBR

Revised

CBRDifference

Combined

CBR (3)

1 M8 1.2 1.1 0.1 205.5 198.8 -6.7 198.8

2 D6 0.3 0.1 0.2 143.9 140.9 -3.0 140.9

3 D8 1.0 0.5 0.5 165.2 153.4 -11.8 153.4

4 P7 2.4 2.2 0.2 154.6 149.9 -4.7 149.9

5 U9 0.7 0.2 0.5 204.3 150.3 -54.0 150.3

6 C6 4.5 4.7 -0.2 150 163.6 13.6 163.6

7 T9 0.5 0.2 0.3 171.7 163.1 -8.6 163.1

8 Q7 0.3 0.3 0.0 170.7 172.0 1.3 172

9 L8 0.8 0.9 -0.1 115.2 116.9 1.7 116.9

10 C8 0.3 0.5 -0.2 140 144.5 4.5 144.5

11 Z6 2.0 1.7 0.3 171.1 162.4 -8.7 162.4

12 K8 0.5 1.0 -0.5 111.7 125.9 14.2 125.9

13 J6 0.6 0.6 0.0 180 180.5 0.5 180.5

14 L5 0.5 0.2 0.3 167.8 162.9 -4.9 162.9

15 F2 0.5 1.3 -0.8 81 157.4 76.4 157.4

16 X5 0.5 0.5 0.0 222.2 222.7 0.5 222.7

17 D9 0.3 0.1 0.2 136.4 133.0 -3.4 133

18 W8 1.6 1.5 0.1 189.9 190.2 0.3 190.2

19 U7 1.2 0.9 0.3 103.9 100.6 -3.3 100.6

20 L6 NR NR NR

21 J7 0.0 0.8 -0.8 152 181.1 29.1 181.1

22 B8 1.1 0.8 0.3 200 190.3 -9.7 190.3

23 S6 3.0 2.9 0.1 130 127.8 -2.2 127.8

24 X8 NR 0.6 180 168.4 -11.6 168.4

25 T2 0.0 1.1 -1.1 87.3 109.3 22.0 109.3

26 Y9 1.3 1.2 0.1 140.5 139.2 -1.3 139.2

27 A2 0.5 0.9 -0.4 146 161.7 15.7 161.7

28 X6 1.0 1.0 0.0 159.6 160.6 1.0 160.6

29 A7 0.2 0.2 0.0 191.9 190.1 -1.8 190.1

30 R5 0.4 136.7 136.7

31 N8 0.4 0.3 0.1 188.8 218.6 29.8 218.6

32 U3 1.1 1.0 0.1 218.6 216.5 -2.1 216.5

33 S7 3.8 3.7 0.1 100 96.8 -3.2 96.8

34 NR

35 M4 0.4 0.3 0.1 155.2 152.7 -2.5 152.7

36 D3 0.7 0.5 0.2 180 163.5 -16.5 163.5

37 G4 0.3 0.2 0.1 130 125.3 -4.7 125.3

38 NR

39 T5 0.6 0.4 0.2 107.6 106.6 -1.0 106.6

40 V3 1.0 0.9 0.1 125.8 NR 17.0 NR

41 M7 0.3 0.3 0.0 NR NR NR

42 E9 0.6 0.6 0.0 NR NR NR

43 J8 0.6 0.3 0.3 150.6 147.4 -3.2 147.4

44 A3 NR 0.0 164 163.3 -0.7 163.3

45 K2 1.3 1.2 0.1 181.7 177.5 -4.2 177.5

46 N3 0.5 0.5 0.0 216.7 218.2 1.5 218.2

See Note (1)

4.2 Sample A - Recalculated CBR results

Code



47 L7 NR NR

48 N9 0.4 0.3 0.1 145.5 146.3 0.8 146.3

49 X3 0.0 0.1 -0.1 122.4 124.4 2.0 124.4

50 N5 173 173

51 Z3 1.0 0.8 0.2 199.7 197.5 -2.2 197.5

52 P6 0.8 0.7 0.1 NR NR NR

53 C4 1.0 0.9 0.1 138.9 137.6 -1.3 137.6

54 NR

55 Y3 212.1 NR NR

56 Q5 1.5 1.0 0.5 135.2 125.4 -9.8 125.4

57 NR

58 K4 1.0 0.9 0.1 162.3 159 -3.3 159

59 V5 1.3 0.4 0.9 252.4 213.2 -39.2 213.2

60 N4 NR 1.9 126.1 131.1 5.0 131.1

61 T8 NR 1.4 161.1 168.1 7.0 168.1

62 C2 1.0 0.7 0.3 180 174.1 -5.9 174.1

63 E4 130 130

64 M3 0.5 0.6 -0.1 180.8 182.4 1.6 182.4

65 R6 1.8 2.0 -0.2 150 156.4 6.4 156.4

66 E5 0.5 0.4 0.1 189.9 189.5 -0.4 189.5

67 X7 1.0 0.7 0.3 170 159.8 -10.2 159.8

68 NR

69 G2 0.8 0.8 0.0 140 146.1 6.1 146.1

70 R7 0.0 0.0 0.0 140 142.2 2.2 142.2

Note (2)

60 55 58

157.4 159.8 159.4

136.6 140.1 138.0

180.2 179.0 176.7

43.6 39.0 38.7

32.3 28.9 28.7

81.0 96.8 96.8

252.4 222.7 222.7

171.4 125.9 125.9

20.5 18.1 18.0

Notes:

1

2

3

3.6.4

Compaction blows either higher or lower than expected 3.6.2

The statistics are different from section 4.1 of the report as result for 47-L7 has been omitted as it

was past the range of the load cell used. Others that exceeded the load cell range are also shaded

green.

Some results could not be recalculated. The combined CBR are these results that could not be

recalculated plus the recalculated results.

Did not meet LDR limit

Did not meet LMR limit

Flagged as needing checking

Exceeded cell capacity - these results omitted

3.6.4

3.3.3

3.5.1

Number of results

See section in report

2.1, 2.4

3.5.7

No Issues

Submitted result had been rounded

Maximum

Range

CV (%)

Median

Third Quartile

First Quartile

IQR

N-IQR

Minimum



Zero

Correction

Revised

CorrectionDifference CBR

Revised

CBRDifference

Combined

CBR (3)

1 M8 1.2 1.2 0.0 195.2 193.9 -1.3 193.9

2 D6 0.5 0.3 0.2 129.1 126.9 -2.2 126.9

3 D8 0.5 0.6 -0.1 208 211.9 3.9 211.9

4 P7 1.8 1.8 0.0 154.6 154.0 -0.6 154

5 U9 0.4 0.7 -0.3 157.4 204.1 46.7 204.1

6 C6 4.1 4.3 -0.2 140 148.9 8.9 148.9

7 T9 0.0 0.1 -0.1 171.8 177.2 5.4 177.2

8 Q7 0.1 0.1 0.0 186.9 188.9 2.0 188.9

9 L8 0.8 1.0 -0.2 112 115.7 3.7 115.7

10 C8 0.2 0.4 -0.2 150 160.2 10.2 160.2

11 Z6 1.7 1.5 0.2 171.1 162.8 -8.3 162.8

12 K8 0.0 0.5 -0.5 131 144.6 13.6 144.6

13 J6 0.9 0.8 0.1 220 215.3 -4.7 215.3

14 L5 0.7 0.4 0.3 155.5 150.2 -5.3 150.2

15 F2 0.5 1.1 -0.6 160.9 183.2 22.3 183.2

16 X5 0.6 0.5 0.1 202 200.6 -1.4 200.6

17 D9 0.4 0.5 -0.1 141.4 142.4 1.0 142.4

18 W8 1.6 1.0 0.6 210 187.8 -22.2 187.8

19 U7 0.9 0.6 0.3 213.3 203.1 -10.2 203.1

20 L6 0.5 0.8 -0.3 184.6 NR NR

21 J7 0.0 0.4 -0.4 119.1 161.7 42.6 161.7

22 B8 1.2 1.1 0.1 180 174.2 -5.8 174.2

23 S6 3.4 3.1 0.3 130 122.8 -7.2 122.8

24 X8 NR 0.8 150 148.2 -1.8 148.2

25 T2 0.0 1.0 -1.0 88.3 108.5 20.2 108.5

26 Y9 1.5 1.5 0.0 150 148.3 -1.7 148.3

27 A2 0.5 0.9 -0.4 150 161.0 11.0 161

28 X6 0.7 0.7 0.0 151.5 152.1 0.6 152.1

29 A7 0.5 0.5 0.0 202 202.3 0.3 202.3

30 R5 0.5 0.8 -0.3 229.7 231.1 1.4 231.1

31 N8 0.3 0.3 0.0 216.6 217.2 0.6 217.2

32 U3 1.1 1.0 0.1 190.1 188.1 -2.0 188.1

33 S7 0.0 0.0 0.0 60 63.7 3.7 63.7

34 NR

35 M4 0.5 0.4 0.1 167.8 165 -2.8 165

36 D3 0.4 0.2 0.2 120 115.4 -4.6 115.4

37 G4 0.4 0.4 0.0 160 160.0 0.0 160.0

38 NR

39 T5 0.0 0.0 0.0 126.5 NR NR

40 V3 0.6 0.6 0.0 126.1 NR 14.0 NR

41 M7 NR NR NR

42 E9 NR NR NR

43 J8 0.0 0.0 0.0 203.8 203.2 -0.6 203.2

44 A3 NR 0.0 188 184 -4.0 184

45 K2 0.3 0.3 0.0 229.7 232.8 3.1 232.8

46 N3 0.6 0.5 0.1 218.2 216.3 -1.9 216.3

4.2 Sample B - CBR results zero-corrected and unrounded

Code

See Note (1)



47 L7 NR NR

48 N9 0.3 0.3 0.0 176.2 175.8 -0.4 175.8

49 X3 0.6 0.6 0.0 196 196.4 0.4 196.4

50 N5 170.6 170.6

51 Z3 0.8 0.8 0.0 186.4 188.1 1.7 188.1

52 P6 0.8 0.8 0.0 226.3 224.7 -1.6 224.7

53 C4 0.8 0.8 0.0 170.7 176.2 5.5 176.2

54 NR

55 Y3 0.9 0.9 0.0 218.7 221.3 2.6 221.3

56 Q5 0.9 0.5 0.4 143.8 137.0 -6.8 137.0

57 NR

58 K4 0.9 0.6 0.3 204.9 205.3 0.4 205.3

59 V5 1.5 0.5 1.0 258.1 217.8 -40.3 217.8

60 N4 NR 1.7 157.9 158.6 0.7 158.6

61 T8 NR 1.8 157.5 156.7 -0.8 156.7

62 C2 1.2 0.8 0.4 170 157.0 -13.0 157.0

63 E4 130 130

64 M3 0.7 0.7 0.0 198 197.9 -0.1 197.9

65 R6 1.4 1.4 0.0 160 159.9 -0.1 159.9

66 E5 1.3 1.3 0.0 151.5 152.6 1.1 152.6

67 X7 1.3 1.3 0.0 180 175.1 -4.9 175.1

68 NR

69 G2 0.8 0.8 0.0 140 136 -4.0 136

70 R7 0.4 0.3 0.1 160 157.9 -2.1 157.9

Note (2)

62 57 59

168.9 174.2 170.6

150.0 152.1 151.2

197.5 200.6 199.3

47.5 48.5 48.1

35.2 36.0 35.7

60.0 63.7 63.7

258.1 232.8 232.8

198.1 169.1 169.1

20.8 20.6 20.9

Notes:

1

2

3

Compaction blows either higher or lower than expected 3.6.2

Did not meet LMR limit 3.6.4

Flagged as needing checking 3.3.3

Exceeded cell capacity - these results omitted 3.5.1

See section in report

No Issues 2.1, 2.4

Did not meet LDR limit 3.6.4

N-IQR

Minimum

Maximum

Range

CV (%)

Number of results

The statistics are different from section 4.1 of the report as result for 47-L7 has been omitted as it

was past the range of the load cell used. Others that exceeded the load cell range are also shaded

green.

Some results could not be recalculated. The combined CBR are these results that could not be

recalculated plus the recalculated results.

Median

Submitted result had been rounded 3.5.7

Third Quartile

First Quartile

IQR



1 M8 206 195 1.4 -0.67 36 D3 180 120 -0.38 -2.76

2 D6 144 129 -0.85 -0.86 37 G4 130 160 -0.55 1.02

3 D8 165 208 0.90 1.56 38 U6

4 P7 155 155 -0.22 -0.24 39 T5 108 127 -1.53 0.55

5 U9 204 157 0.70 -2.21 40 V3 126 126 -1.22 -0.23

6 C6 150 140 -0.55 -0.66 41 M7

7 T9 172 172 0.38 -0.24 42 E9

8 Q7 171 187 0.63 0.44 43 J8 151 204 0.57 2.00

9 L8 115 112 -1.65 -0.37 44 A3 164 188 0.53 0.77

11 Z6 171 171 0.36 -0.24 46 N3 217 218 1.98 -0.18

12 K8 112 131 -1.38 0.57 47 L7 131 160 -0.54 0.99

13 J6 180 220 1.37 1.44 48 N9 146 176 0.00 1.05

14 L5 168 156 0.03 -0.76 49 X3 122 196 -0.06 2.85

15 F2 81 161 -1.39 3.12 # 50 N5 173 171 0.38 -0.34

16 X5 222 202 1.79 -1.09 51 Z3 200 186 1.13 -0.80

17 D9 136 141 -0.77 -0.03 52 P6

19 U7 104 213 -0.08 4.36 # 54 Z9

20 L6 55 Y3 212 219 1.91 0.04

21 J7 152 119 -0.88 -1.62 56 Q5 135 144 -0.75 0.12

22 B8 200 180 1.02 -1.08 57 T7

23 S6 130 130 -1.08 -0.24 58 K4 162 205 0.80 1.55

24 X8 180 150 0.15 -1.50 59 V5 252 258 3.30 # 0.00

25 T2 87 88 -2.55 -0.20 60 N4 126 158 -0.66 1.10

26 Y9 141 150 -0.55 0.16 61 T8 161 158 -0.05 -0.39

27 A2 146 150 -0.45 -0.07 62 C2 180 170 0.49 -0.66

28 X6 160 152 -0.19 -0.58 63 E4 130 130 -1.08 -0.24

29 A7 192 202 1.26 0.18 64 M3 181 198 1.00 0.48

30 R5 137 230 0.78 3.67 # 65 R6 150 160 -0.20 0.18

31 N8 189 217 1.46 0.93 66 E5 190 152 0.34 -1.85

32 U3 219 190 1.52 -1.44 67 X7 170 180 0.49 0.18

33 S7 100 60 -2.83 -1.92 68 S4

34 Q2 69 G2 140 140 -0.73 -0.24

35 M4 155 168 0.02 0.29 70 R7 140 160 -0.38 0.60

Note: A # indicates an outlier where the z-score obtained is either greater then 3 or less than -3. Codes for all participates are shown. Results where only one value

was submitted have been left out. The results column shows a blank entry for those participants that did not perform this test. Minimum, Maximum and Range are

calculated with outliers excluded.

WithinSample A Sample B

Between Within

Laboratories Laboratory Laboratories Laboratory

4.3 CBR - Repeatability: Z - Scores

Code

Test Results (%) Z Score

Code

Test Results (%) Z Score

Sample A Sample BBetween



Statistic Sample A Sample B

Number of results 61 61

Median 155 161

First Quartile 136 150

Third Quartile 180 196

IQR 43.6 46.0

Normalised IQR 32.3 34.1

CV (%) 20.8 21.2

Minimum 81 60

Maximum 222 258

Range 141 198

4.3 CBR - Repeatability: Z - Scores



M8 205.5 3.41 # T2 87.3 -4.60 # X3 122.4 -2.22

D6 143.9 -0.77 Y9 140.5 -1.00 N5 173.0 1.21

D8 165.2 0.68 A2 146.0 -0.62 Z3 199.7 3.02 #

P7 154.6 -0.04 X6 159.6 0.30 P6 NR

U9 204.3 3.33 # A7 191.9 2.49 C4 138.9 -1.11

C6 150 -0.35 R5 136.7 -1.25 Z9 NR

T9 171.7 1.12 N8 188.8 2.28 Y3 212.1 3.86 #

Q7 170.7 1.05 U3 218.6 4.30 # Q5 135.2 -1.36

L8 115.2 -2.71 S7 100 -3.74 # T7 NR

C8 140 -1.03 Q2 NR K4 162.3 0.48

Z6 171.1 1.08 M4 155.2 0.00 V5 252.4 6.59 #

K8 111.7 -2.95 D3 180 1.68 N4 126.1 -1.97

J6 180 1.68 G4 130.0 -1.71 T8 161.1 0.40

L5 167.8 0.85 U6 NR C2 180 1.68

F2 81.0 -5.03 # T5 107.6 -3.23 # E4 130 -1.71

X5 222.2 4.54 # V3 125.8 -1.99 M3 180.8 1.74

D9 136.4 -1.27 M7 NR R6 150 -0.35

W8 189.9 2.35 E9 NR E5 189.9 2.35

U7 103.9 -3.48 # J8 150.6 -0.31 X7 170 1.00

L6 NR A3 164 0.60 S4 NR

J7 152.0 -0.22 K2 181.7 1.80 G2 140.0 -1.03

B8 200 3.04 # N3 216.7 4.17 # R7 140.0 -1.03

S6 130 -1.71 L7 130.7 -1.66

X8 180 1.68 N9 145.5 -0.66


Median 155.2

Median MU 2.4



IQR 43.6

Set SD 14.8

CV (%) 9.5

Minimum 111.7 (81.0)

Maximum 191.9 (252.4)

Range 80.2 (171.4)

4.4 CBR - Sample A - Set SD: Z - Scores

Statistic Value





Code

Test

Result

%

Z Score Code

Test

Result

%

Z ScoreCode

Test

Result

%

Z Score



M8 195.2 1.72 T2 88.3 -4.99 # X3 196.0 1.77

D6 129.1 -2.43 Y9 150.0 -1.12 N5 170.6 0.18

D8 208 2.52 A2 150.0 -1.12 Z3 186.4 1.17

P7 154.6 -0.83 X6 151.5 -1.02 P6 226.3 3.67 #

U9 157.4 -0.65 A7 202.0 2.15 C4 170.7 0.18

C6 140 -1.74 R5 229.7 3.88 # Z9 NR

T9 171.8 0.25 N8 216.6 3.06 # Y3 218.7 3.19 #

Q7 186.9 1.20 U3 190.1 1.40 Q5 143.8 -1.51

L8 112.0 -3.50 # S7 60 -6.76 # T7 NR

C8 150 -1.12 Q2 NR K4 204.9 2.33

Z6 171.1 0.21 M4 167.8 0.00 V5 258.1 5.66 #

K8 131 -2.31 D3 120 -3.00 N4 157.9 -0.62

J6 220 3.27 # G4 160.0 -0.49 T8 157.5 -0.65

L5 155.5 -0.77 U6 NR C2 170 0.14

F2 160.9 -0.43 T5 126.5 -2.59 E4 130 -2.37

X5 202.0 2.15 V3 126.1 -2.62 M3 198.0 1.89

D9 141.4 -1.66 M7 NR R6 160 -0.49

W8 210 2.65 E9 NR E5 151.5 -1.02

U7 213.3 2.85 J8 203.8 2.26 X7 180 0.77

L6 184.6 1.05 A3 188 1.27 S4 NR

J7 119.1 -3.06 # K2 229.7 3.88 # G2 140 -1.74

B8 180 0.77 N3 218.2 3.16 # R7 160.0 -0.49

S6 130 -2.37 L7 160.0 -0.49

X8 150 -1.12 N9 176.2 0.53


Median 167.8

Median MU 2.5



IQR 47.0

15.9

CV (%) 9.5

Minimum 120.0 (60.0)

Maximum 213.3 (258.1)

Range 93.3 (198.1)





Code

Test

Result

%

Z Score Code

Test

Result

%

Z ScoreCode

Test

Result

%

Z Score

4.4 CBR - Sample B - Set SD: Z - Scores

Statistic Value

Set SD



5. Program information 5.1 Z score Summary The proficiency program was conducted in September/October 2016. A ‘Z-score Summary’ summary was issued on the 12 December 2016. A copy was e-mailed to all participants who submitted results. The summary is intended as an early indicator of participant performance. This program report supersedes the z - score summary. Further information can be found in section 5.9 ‘Statistics’. The z-scores generally do not vary significantly between the “summary” and the “Final Report”. Following review of the submitted results several results were rejected but it did not significantly affect the statistics. 5.2. Program Design 5.2.1 Design

This program is one of a series of CBR programs conducted by LabSmart Services over the last ten years. Proficiency testing programs have shown that the CBR test produces a wide variation in results. Part of the design of each program involves asking for the right information. The correct analysis of the data collected then allows feedback to be offered to enable participants to improve in the performance of this test. The program was designed to provide technical feedback regarding performance as well as possible improvements in performance. Other considerations involving the design of the program are detailed below. 5.2.2 Selection of material for the program

The test in this proficiency program is operator skill/experience dependant. Different materials are selected for each program to mirror the range of materials encountered in practice and hence the results obtained. This program provides a sample that gives results in the range that would be commonly tested by laboratories. The higher the CBR value the greater the variation encountered. Although a lower CBR material was desirable preliminary testing can be misleading as shown by the program outcome. For this material CBR results varying from 80 to 250% were possible. Comments under “Comparing Statistics” should be considered. It is expected that the level of experience/skill need to perform these tests will present a reasonable assessment of the overall competency of the tester and industry performance.



5.2.3 OMC & MDD

The determination of OMC and MDD is usually an initial stage undertaken prior to performing a CBR test. The determination of these two parameters can show a significant variation. In turn having an impact on the variation obtained for CBR results. The intention of the program is to minimise the influence on the CBR results that could arise from laboratories determining these values in-house and reduce the likelihood of different OMC and MDD values being applied. To assist in reducing this variation, participants were requested to use 100% standard compaction and use:

OMC = 8.6%

MDD = 2.260 t/m3. Although this has been the approach to try and minimise variation other aspect may still contribute to the variation observed. OMC/MDD values may vary from person to person but this may not be so important if the same person determines OMC/MDD and CBR. That is a low compaction on the OMC/MDD should give the same compaction on the CBR. Overall it is still considered that a set OMC/MDD will contribute the least variation. 5.2.4 Role of proficiency testing

The determination of outliers is an important task of this proficiency program. A secondary function is to provide feedback that can help those with outliers identify possible areas to investigate as well as assist all participants to improve. In addition to the statistics, proficiency programs often obtain other information that is not normally available to a laboratory. It allows for a better understanding of the testing and can provide information that can lead to improvements in the testing process or test method. Proficiency testing enables participants to measure competency against others. It is also a measure of staff performance and the equipment used. Apart from ‘measurement uncertainty’ it is the next most useful tool a laboratory has in better understanding the performance of a test. 5.2.5 Participant assessment

Assessment of each participant is based on a z-score that is related to the program consensus value (median). This is used to determine any statistical outliers. Compliance to proficiency program requirements including the correct calculation of results and adherence to program and test method requirements may also be used as part of the assessment process. Participants may also be asked to investigate any discrepancies detected with the paperwork submitted.



2.2.6 Reporting of results - Significant figures

The number of decimal places (significant figures) reported for a test has a bearing on the statistical analysis and therefore the interpretation of the results. There is a need to strike a balance between what is desirable from a statistical viewpoint and test method accuracy while recognising how the results are used in practice. Too few decimal places (e.g. due to rounding) can cause an increase in the observed spread of results. Increasing the number of decimal places (with respect to normal reporting) can distort the observed spread of results compared to that encountered in actual practice. Large numbers of similar, rounded results can also cause a distortion in the analysis. For example rounding to 10 % means that any number between 45 and 55 will become 50%. If the largest value is 45 in a set of results it is pushed out to 50 through rounding. Rounded results may better reflect the repeatability and reproducibility of the test according to the rounding in the test method but are not as useful when considering laboratory performance. For this program, it was decided that the benefits of using additional decimal places would complement the aim of the proficiency program. Participants results were analysed as received regardless of whether there were more or less significant figures than the number requested by the program. 2.2.7 Additional information requested

This program requested additional information as detailed in Section 6 not usually reported. The additional information is however consistent with the performance of the test and the records the test method requires laboratories to maintain. The additional information is used to interpret participant’s performance and assist with providing technical comment including feedback on outliers and possible participant improvement.

5.3. Sample preparation Sufficient material of a homogeneous appearance was obtained for the proficiency program. The lot was partially dried then mixed to ensure, as far as possible, a homogeneous material throughout. The material was sampled and placed into numbered plastic bags. Ten samples were drawn at regular intervals from the lot for homogeneity testing. Each participant received a randomly drawn sample from the remaining samples. A unique program code was assigned to each sample.

5.4. Packaging and instructions Each plastic bag was sealed with a rubber band and placed into a sturdy box. Each participant received one box with a sealed sample labelled ‘2016 (67) CBR Sample’.



The sample weighed approximately 14.8 kg. Instructions and a ‘results log’ sheet were enclosed (See Appendix A & B). Participants were instructed to test according to the nominated test method and report to the accuracy indicated on the ‘Results Log’.

5.5. Quarantine There were three samples that required additional preparation to meet WA quarantine requirements.

5.6. Sample despatch Samples were dispatched to participants between the 13 & 16 September 2016 via courier. Dispatched samples were tracked from ‘despatch to delivery’ for each participant.

5.7. Homogeneity testing Homogeneity samples were selected, evenly spaced, from the prepared participant samples. Samples for homogeneity testing were packed in the same way as those for all participants. The homogeneity samples were tested by an independent NATA accredited laboratory. To approximate the same conditions the same instructions were given to the laboratory performing the homogeneity testing. Ten samples were tested for homogeneity. The wide variation in results that arise from CBR testing can also occur with homogeneity testing particularly at high CBRs. One of the ten samples (H3) was very low and rejected on a statistical level. The result may have been affected by the soaking process. The overall variability associated with the homogeneity samples was considered satisfactory. The average of the homogeneity samples also lies within 1 s.d of the participant’s median value. This provides confidence that any outliers identified in the program represent statistically valid outliers. A statistical analysis of the homogeneity testing results is provided in table 5.7A.

5.8. Participation Seventy participants from around Australia entered the program. Sixty-five participants returned results. Participants were requested to return results by 12 October 2016.

5.9. Statistics Z-Scores were calculated for each test and used to assess the variability of each participant relative to the consensus median. A corresponding z-score graph was produced for each test.



The use of median and quartiles reduces the effect that outliers have on the statistics and other influences. Therefore, z-scores provide a more realistic or robust method of assessment.

Code

Bearing Ratio

CBR Rounded

CBR 2.5 mm 5.0 mm

% %

H1 101.7 136.0 136.0 140

H2 108.2 145.1 145.1 150

H3 R R

H4 112.4 150.6 150.6 150

H5 95.9 123.9 123.9 120

H6 101.1 135.8 135.8 140

H7 104.9 138.2 138.2 140

H8 101.8 137.7 137.7 140

H9 99.1 131.6 131.6 130

H10 94.1 122.3 122.3 120

Mean 102.1 135.7 135.7 137

Standard Deviation 5.7 9.1 9.1 11

Range 30.6 46.4 46.4 50

Coefficient of Variation (%) 5.6 6.7 6.7 8

Table 5.7A Homogeneity results

Some results were reported by participants to more decimal places than requested as part of the proficiency program and by others to fewer decimal places. In all instances test results have been used as submitted by participants. Assessment of participant’s data is undertaken to ensure data is statistically comparable. Checks are undertaken to ensure the data calculated matches that reported by the participant and that the appropriate corrections etc. have been applied if required. The level of checking required varies from program to program. If inconsistencies are identified the data may be removed or amended with the discrepancy highlighted.

A z-score is one way of measuring the degree of consensus with respect to the grouped test results. The z-scores in this report are an approximate of the standard deviation. For each test a z-score graph is shown. Use the graph to visually check statistically how you compare to other participants.



The following bar (Figure 5.9A) is shown at the bottom of each graph. This helps to quickly visualize where each participant’s results falls.

Review Weak

Consensus Strong Consensus

Weak Consensus

Review

Figure 5.9A Z-score interpretation bar

For example:

A strong consensus (i.e. agreement) means that your test result is close i.e. within

1 standard deviation of the median.

A weak consensus means that your test result is satisfactory and is within 2

standard deviations of the median.

If you have obtained a test result that is outside 2 standard deviations then it may be

worth reviewing your testing processes to ensure that all aspects are satisfactory.

Only those obtaining a z-score approaching 3 (I.e. outside 2.75 range) have been highlighted in the report for review.

If you have obtained a test result that is outside 3 standard deviations then you will need to investigate your testing processes to ensure that all aspects are satisfactory. Participant assessment is not based purely on statistical analysis. Compliance to proficiency program requirements including the correct calculation of results and adherence to program requirements may also be used as part of the assessment process. Participants may also be asked to investigate any discrepancies detected with the paperwork submitted. For further details on the statistics used in this proficiency program can be obtained from LabSmart Services or download the ‘Participant Guide’ from the LabSmart Services website. 5.9.1 Z-score summary

A “Z-Scores Summary” is issued soon after most results are received. It gives participants early feedback as to any program outliers. The summary is available on the LabSmart Services website up until the final report is issued. The final report supersedes the z-score summary. The final report contains detailed technical feedback regarding the performance of tests and revised z-scores. The inclusion of late results or corrections are at the discretion of the program coordinator. In some instances, this may change some of the z-scores slightly but generally the performance outcome remains the same. If there is any impact it will be discussed within section 5.1 of the report. 5.9.2 Comparing statistics from one program to another

The statistics generated from one proficiency program are not usually comparable to those from another proficiency testing program. Only very general comparisons may be possible. The reason statistics from one program may not be compared to another is due to the range of variables that differ from one proficiency program to another.



These variables include:

Type of material selected,

The number of participants,

Experience of participants,

Test methodology variations,

Equipment used,

Test methods used,

Experience of supervisors,

Range of organisations involved.

Program design and the statistics employed. The program outcome represents a ‘snap shot’ of the competency within the industry and hence provides an overview of the industry. The more participants involved in the program then the more representative the overview. 5.9.3 Measurement uncertainty

The statistics detailed in this program do not replace the need for laboratories to separately calculated measurement uncertainties associated with each test when required by the client or NATA. The proficiency program does give information useful for calculating the MU and bench marking the MU calculated. 5.9.4 Metrological traceability

The assigned median value used in this proficiency testing program is derived from participant performance and is not metrologically traceable.



This page has been left blank intentionally for formatting purposes.



Code M8 D6 D8 P7 U9 C6 T9

Moisture-Before compaction, Cl 6(c) (%) 8.5 8.4 8.7 5.9 8.5 8.5 8.5

Moisture Content Variation (Wv) (%) 0.1 0.2 0.1 2.7 0.1 0.1 -0.1

Compaction (Manual or Auto) M M M M A M M

Compaction Method - Standard (Y/N) Y Y Y Y Y Y Y

No. blows per layer 43/38/46 53/55/57 100/100/100 53/53/53 NR 119/116/112 50/50/50

Dry Density g/cm3 2.259 2.257 2.258 2.254 2.281 2.262 2.261

Density Ratio (LDR) % 99.9 99.9 99.9 99.8 100.9 100.1 100.1

Moisture Ratio (LMR) % 98.8 97.7 100.7 100.0 98.8 98.8 99.0

BR @ 2.5 mm (%) 174.7 121.2 131.8 117.5 157.3 120 166.7

BR @ 5.0 mm (%) 205.5 143.9 165.2 154.6 204.3 150 171.7

CBR (%) 205.5 143.9 165.2 154.6 204.3 150 171.7

Correction (mm) 1.2 0.3 1.0 2.4 0.7 4.5 0.5

Swell (%) -0.1 -0.1 0 -0.5 0.0 -0.3 -0.2

Moisture ww 9.2 NR 9.8 9.3 8.7 10.7 8.9

Moisture w30 8.6 8.9 9.3 9.0 8.9 8.3 8.6

Moisture wr 8.4 8.3 NR 8.7 7.5 8.5 8.2

Date last calibrated 4/04/16 30/03/16 April 2016 8/06/16 2/07/15 26/11/15 30/08/16

Calibrated range (kN) 0-50,000N 0-50kN 0-50kN 0-50kN 0-100kN 0.01-50kN 0-50kN

Load cell (C) or ring (R) C C C C C C C

Calibration Class (AA, A, B, C etc) C NR A C AA/A A AA

Hand driven (H) or motorised (M) M M M M M M M

Rate of penetration (mm/min) 1mm/min 1mm/min 1.00mm/min 1.02mm/min 1mm/min 1.09mm/min 1.0mm/min

Seating load applied (N) 23N 250N 0.044kN 250N 4.5kg 0.240kN 35N

Seating load set to zero (Y/N) Y Y Y Y Y Y Y

Period Cured (hours) 48 48+ 48 48 49 72 72

Graph computer or hand (C/H) C C C C NR C C

Condition of material Moist Good Dry Dry Good Good Moist

Loads in ( N or kN ) N N kN kN kN kN kN

0 0 0 0.469 0 0.000 0.02 0

0.5 167 1573 2.387 0.047 1.4240 0.05 1.191

1 960 5321 4.159 0.226 4.0609 0.06 5.485

1.5 3870 8562 6.232 0.694 7.4279 0.09 12.338

2 8548 11666 8.817 1.678 10.9349 0.20 15.821

2.5 12910 14455 11.504 3.199 14.1340 0.33 18.771

3 17772 17298 14.646 5.199 17.466 0.45 21.626

3.5 21686 19827 17.882 7.865 20 0.84 24.111

4 25663 22339 21.002 10.940 23.4102 1.56 26.660

4.5 29011 24900 24.209 13.392 26 2.74 29.111

5 32766 27491 27.131 16.323 28.9849 4.38 31.424

6 39611 32643 33.150 22.563 33 9.50 36.104

7.5 48601 39682 40.649 31.091 41.3022 19.02 43.006

8 NR 42098 42.999 34.025 43 22.09 NR

10 NR NR 48.961 45.227 52.3948 33.39 NR10.512.5 NR NR NR NR 63.4330 47.04 NR


Number 1 2 3 4 5 6 7

6.0 Particpants Test Results - Sample A

Section 1 of 8 Note: Blank or NR = No result returned, Green are calculated/corrected results by PT coordinator.

D8 , Values provided above do not correspond to

penetration values shown here.



Code Q7 L8 C8 Z6 K8 J6 L5


Moisture Content Variation (Wv) (%) 0.2 0.2 99.8 0.0 0.0 0.3 0.3

Compaction (Manual or Auto) M M M M M M M


No. blows per layer 53/53/53 53/53/53 53/53/60 53/53/53 80/100/80 65/65/68 56

Dry Density g/cm3 2.283 2.256 2.261 2.266 2.263 2.266 2.265



BR @ 2.5 mm (%) 131.8 84.4 100 132.1 73.8 140 153.2

BR @ 5.0 mm (%) 170.7 115.2 140 171.1 111.7 180 167.8

CBR (%) 170.7 115.2 140 171.1 111.7 180 167.8

Correction (mm) 0.3 0.82 0.291 2.0 0.5 0.6 0.5

Swell (%) 0.0 -0.3 0.0 0.3 -0.4 0.0 -0.1

Moisture ww 8.6 8.4 8.6 9.0 8.6 NR 9.4

Moisture w30 8.8 8.8 8.7 8.6 8.7 8.8 8.7

Moisture wr 8.6 8.7 8.4 8.6 8.4 8.5 8.8

Date last calibrated 7/12/15 14/07/15 7/10/16 29/10/14 18/09/15 6/05/16 22/05/16

Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0-50kN 0.2-40kN 0-50kN 0-50kN


Calibration Class (AA, A, B, C etc) A AA A/B/C A A A A

Hand driven (H) or motorised (M) M M M M H M H

Rate of penetration (mm/min) 1mm/min 1.0mm/min 1mm/min 1.0mm/min 1mm/min 1.0mm/min 1mm/min

Seating load applied (N) 246N 0.105 256 45N 0.25kN 250N 250kN


Period Cured (hours) 240 72 59 12 144 74 72

Graph computer or hand (C/H) H C C C NR C C

Condition of material Dry Good Moist Acceptable Good Sealed Moist

Loads in ( N or kN ) N kN kN N kN kN N

0 0 0.000 0 0 0 0.00 0.000

0.5 2096 0.561 1.28 221 1.0 1.62 1366

1 4895 1.557 3.40 819 2.32 3.97 4740

1.5 8290 3.179 6.50 2209 3.74 6.74 9342

2 11780 5.262 8.76 4314 5.55 10.30 13614

2.5 15320 7.456 11.20 6608 7.54 13.93 17304

3 18755 9.674 14.08 9200 9.74 17.52 20316

3.5 22235 12.058 17.00 11790 12.21 21.11 23040

4 25623 14.595 20.08 14624 14.76 24.53 25768

4.5 28975 17.062 23.20 17496 17.20 28.02 28660

5 32004 19.315 25.49 20810 19.62 31.53 31090

6 37850 23.549 31.40 27558 24.64 38.54 35550

7.5 46222 29.720 39.11 36998 32.12 47.79 42042

8 48970 31.503 41.65 40008 34.55 50.65 43708

10 NR 38.504 50.88 51412 NR NR NR10.512.5 NR 46.058 NR 62009 NR NR NR


Number 8 9 10 11 12 13 14

6.0 Particpants Test Results - Sample A 6.0 Particpants Test Results - Sample A




Code F2 X5 D9 W8 U7 L6 J7


Moisture Content Variation (Wv) (%) 0.1 0.2 0.2 2.2 -0.1 0.2 0.1



No. blows per layer 66/67/64 53/55/56 40/40/40 30/28/31 NR 53 52/52/53

Dry Density g/cm3 2.259 2.275 2.260 2.2598 2.246 2.262 2.259


Moisture Ratio (LMR) % 101.2 97.7 98 100.0 101.2 97.7 98.6

BR @ 2.5 mm (%) 81.0 181.8 121.2 147.2 90.4 180.4 93.5

BR @ 5.0 mm (%) 130.9 222.2 136.4 189.9 103.9 NR 152.0

CBR (%) 81.0 222.2 136.4 189.9 103.9 NR 152.0

Correction (mm) 0.50 0.5 0.3 1.6 1.2 0.5 0

Swell (%) 0.0 0.0 0.0 0.0 0.0 0.0 -0.1

Moisture ww 9.5 9.3 9.3 8.5 9.7 8.4 9.3

Moisture w30 9.3 8.7 8.6 8.7 9.0 8.6 8.9

Moisture wr 8.5 8.3 8.3 NR 8.4 9.7 8.2

Date last calibrated 22/12/15 11/10/14 9/10/15 27/04/16 16/05/16 22/07/15 May 2016

Calibrated range (kN) 0-50kN 0-50kN 0-50kN 50kN 0.001-50kN 0-40kN 0-50kN


Calibration Class (AA, A, B, C etc) A/B A A A/B/C A A A


Rate of penetration (mm/min) 1.0mm/min 1.0mm/min 1.0mm/min 1mm/min 0.99mm/min 1.0mm/min 1.0mm/min

Seating load applied (N) 45N 0.25kN 0.25kN 20N 250N 0.250 NR


Period Cured (hours) 70.5 148 48 96 48 48 56

Graph computer or hand (C/H) C C C C C C C

Condition of material Moist Good Good Sealed Good Good Good

Loads in ( N or kN ) N N N N kN N kN

0 0 0 0 0 0.000 0.0 0

0.5 305 1280 1450 149 0.594 1862 0.748

1 1206 4480 4260 828 1.356 5588 2.357

1.5 2924 9180 7840 2138 2.513 10322 5.022

2 5163 14060 11290 4488 4.095 15240 8.625

2.5 7809 19240 14190 7334 6.189 19680 12.347

3 10689 23540 16910 11068 8.645 23810 15.981

3.5 13712 27650 NR 14880 10.928 27590 19.495

4 16646 32330 21400 22567 13.082 31140 23.022

4.5 19648 35980 NR 26420 15.014 34480 26.663

5 22693 39780 25760 30282 16.830 37530 30.095

6 29237 48800 NR 33680 19.947 NR 36.397

7.5 38597 NR 34010 43645 24.380 NR 45.328

8 41319 NR NR NR 25.746 NR 48.038

10 NR NR 41360 58025 31.394 NR 58.72510.512.5 NR NR 47120 NR 38.857 NR NR


Number 15 16 17 18 19 20 21





Code B8 S6 X8 T2 Y9 A2 X6


Moisture Content Variation (Wv) (%) -0.1 0.1 NR 0.0 0.0 0.2 -0.2

Compaction (Manual or Auto) M M M M M M A


No. blows per layer 55/44/44 53/53/53 53/53/53 53/53/53 53/53/53 44/55/60 80/75/75

Dry Density g/cm3 2.262 2.272 2.215 2.259 2.258 2.257 2.263

Density Ratio (LDR) % 100.1 100.5 98 100.0 100.0 100 100.1


BR @ 2.5 mm (%) 160 100 NR 48.9 109.5 108.0 116.3

BR @ 5.0 mm (%) 200 130 180 87.3 140.5 146.0 159.6

CBR (%) 200 130 180 87.3 140.5 146.0 159.6

Correction (mm) 1.097 3.052 NR 0.0 1.3 0.5 1.00

Swell (%) 0.0 0.0 -2.5 0.0 -0.5 0.0 NR

Moisture ww 9.1 8.3 NR 108.8 8.7 9.7 8.5

Moisture w30 8.9 8.9 NR 100.9 8.6 9.1 8.5

Moisture wr 8.5 8.2 NR 98.3 8.1 8.6 8.5

Date last calibrated May 2015 3/06/16 25/05/15 6/01/15 1/03/15 June 2015 23/08/16

Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0-50,000N 0-50kN 0.045-50kN 0-50kN

Load cell (C) or ring (R) C R C C C C C

Calibration Class (AA, A, B, C etc) NR AA/B A A A/B/C A A/B


Rate of penetration (mm/min) 0.89 1.06 1 1.00mm/min 1mm/min 1mm/min 1.00mm/min

Seating load applied (N) 0.05kN 21 0.25kN 45 0 0.045 0

Seating load set to zero (Y/N) N N N Y N Y Y


Graph computer or hand (C/H) C C C C C H H

Condition of material OK Damp Damp Good Good Good Good

Loads in ( N or kN ) kN N kN N kN kN N

0 0.05 0.21 0.25 45 0.0 NR 0

0.5 0.78 0.68 1.34 194 0.19 0.390 660

1 2.68 1.40 3.36 731 0.98 1.600 1890

1.5 5.48 2.30 6.09 2000 2.45 3.800 3810

2 8.81 3.29 9.14 3980 4.69 7.150 6280

2.5 12.38 4.41 12.42 6460 7.16 10.600 9090

3 16.40 5.60 15.79 8780 9.95 14.400 12200

3.5 20.68 6.83 19.37 11180 12.63 17.500 15350

4 24.72 8.08 22.91 13320 15.52 20.700 18600

4.5 28.43 9.36 26.36 15390 18.40 23.800 22000

5 32.11 10.63 29.70 17280 21.22 26.500 25260

6 38.87 16.30 35.88 20870 26.27 32.250 31600

7.5 49.64 23.56 43.94 26670 33.40 40.000 40150

8 NR 26.18 46.69 28690 NR 42.300 42900

10 NR 35.61 NR 37240 43.95 NR 5300010.5 -76.1912.5 NR 44.40 NR 47890 NR NR 62800


Number 22 23 24 25 26 27 28






Code A7 R5 N8 U3 S7 Q2 M4

Moisture-Before compaction, Cl 6(c) (%) 8.4 8.2 8.3 8.4 8.3 8.6

Moisture Content Variation (Wv) (%) 0.2 0.4 0.3 NR 0.3 0.0

Compaction (Manual or Auto) M M M M M M

Compaction Method - Standard (Y/N) Y Y Y Y Y Y

No. blows per layer 50/50/50 41/42/44 56/56/57 53/53/53 25/39/30 53/53/53

Dry Density g/cm3 2.260 2.270 2.265 2.259 2.264 2.260

Density Ratio (LDR) % 100.0 100.3 100.2 99.9 100.2 100.1

Moisture Ratio (LMR) % 97.7 95.3 96.5 97.7 96.1 99.9

BR @ 2.5 mm (%) 155.3 94.9 153.6 176.0 80 124.2

BR @ 5.0 mm (%) 191.9 136.7 188.8 218.6 100 155.2

CBR (%) 191.9 136.7 188.8 218.6 100 155.2

Correction (mm) 0.2 0.4 0.4 1.1 3.8 0.4

Swell (%) 0.1 0.0 -0.06 0.17 0.0 0.0

Moisture ww NR 9.0 9.3 8.8 9.5 NR

Moisture w30 7.8 8.9 8.8 9.6 9.0 8.9

Moisture wr NR 8.1 8.3 8.8 9.2 8.5

Date last calibrated 18/08/16 18/11/15 9/02/15 11/10/16 3/03/15 4/03/15

Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0-50kN 0-50kN 0.2-50kN

Load cell (C) or ring (R) C C C C C C

Calibration Class (AA, A, B, C etc) A/B A AA A/B/C A A/B/C

Hand driven (H) or motorised (M) M M M H M M

Rate of penetration (mm/min) 1mm/min 1.0mm/min 1.0mm/min 1mm/min 1mm/min 1mm/min

Seating load applied (N) 0.25kN 50N 45N 0.04 0.1kN 0.050kN

Seating load set to zero (Y/N) Y N Y N Y Y

Period Cured (hours) 48 48 48 48 50 48

Graph computer or hand (C/H) H H C C C C

Condition of material Good Moist Suitable Good Moist NR

Loads in ( N or kN ) kN kN kN kN N N

0 0.0 0.0 0 NR 0 0.000

0.5 1.79 0.64 1.133 0.39 164 2211

1 5.73 2.31 4.709 1.59 379 4432

1.5 10.22 4.97 9.386 4.24 585 7263

2 15.05 8.19 13.372 8.43 867 10475

2.5 19.02 11.35 17.275 13.16 1285 13899

3 22.78 14.69 20.959 17.89 1947 17023

3.5 26.42 17.50 24.480 22.32 2588 20236

4 29.78 20.30 27.827 26.53 3297 23189

4.5 33.69 23.40 31.238 31.12 4192 26083

5 36.06 26.07 34.725 35.04 5400 28717

6 42.00 31.62 41.047 42.68 8974 34099

7.5 50.00 39.06 49.787 NR 14795 42563

8 NR 41.55 NR NR 16679 45444

10 NR 49.96 NR NR 24062 NR10.512.5 NR NR NR NR 32034 NR


Number 29 30 31 32 33 34 35

Note: Blank or NR = No result returned, Green are calculated/corrected results by PT coordinator. Section 1 of 8




Code D3 G4 U6 T5 V3 M7 E9


Moisture Content Variation (Wv) (%) 100.0 0.0 0.1 0.2 0.1 0.2

Compaction (Manual or Auto) M M M M M A


No. blows per layer 53/53/53 50 53/53/53 53/53/53 53/53/53 53/53/48

Dry Density g/cm3 2.260 2.260 2.261 2.259 2.264 2.261

Density Ratio (LDR) % 100 99.8 100.0 100.0 100.2 100.0

Moisture Ratio (LMR) % 100 100.0 98.8 100.0 98.8 97.7

BR @ 2.5 mm (%) NR 100.0 94.7 114.1 135.2 164.7

BR @ 5.0 mm (%) 180 130.0 107.6 125.8 NR NR

CBR (%) 180 130.0 107.6 125.8 NR NR

Correction (mm) 0.7 0.3 0.55 1.00 0.33 0.6

Swell (%) 0.0 -0.5 0.0 0.0 0.00 0.0

Moisture ww 9.6 9.4 NR NR NR 8.4

Moisture w30 9.0 8.9 9.3 8.8 9.0 8.5

Moisture wr 8.6 8.3 8.7 8.7 8.7 8.4


Calibrated range (kN) 100kN 0-50kN 0.2.-250kN 0-250kN 0.2-250kN 0-25kN


Calibration Class (AA, A, B, C etc) A AA A/AA C-AA A/AA AA

Hand driven (H) or motorised (M) M M M M M M

Rate of penetration (mm/min) 1mm/min 1.0mm/min 1mm/min 0.99mm/min 1mm/min 1mm/min

Seating load applied (N) 250N 0.250 250N 200N 250N 40N

Seating load set to zero (Y/N) Y Y Y Y Y Y

Period Cured (hours) 48-50 48 72 72 72 50

Graph computer or hand (C/H) C NR C C C C

Condition of material Dry Sealed Moist Moist Moist Good

Loads in ( N or kN ) N kN kN kN kN kN

0 9.93 0 -0.001 -0.001 0.000 0.009

0.5 1205.4 1.278 0.902 0.363 1.528 0.748

1 4224.3 3.914 2.325 1.488 4.938 3.661

1.5 10261.2 6.670 4.826 3.490 8.696 8.160

2 16659.6 9.279 7.564 6.229 10.687 12.802

2.5 20671.7 11.961 10.028 9.151 15.683 17.149

3 23238.1 14.423 12.318 12.091 19.096 21.071

3.5 25282.6 16.758 14.341 15.066 22.356 24.742

4 27012.1 19.188 16.190 17.913 25.091 24.377

4.5 28671.4 21.507 18.005 20.574 NR NR

5 30224.9 23.766 19.539 23.297 NR NR

6 33071.4 28.685 22.779 NR NR NR

7.5 36851.2 35.890 25.041 NR NR NR

8 38400.9 38.294 NR NR NR NR

10 43781.6 47.804 NR NR NR NR10.5 NR NR12.5 50200.1 NR NR NR NR NR


Number 36 37 38 39 40 41 42





Code J8 A3 K2 N3 L7 N9 X3


Moisture Content Variation (Wv) (%) -0.4 -0.3 0.2 0.2 0.0 0.0 0

Compaction (Manual or Auto) A A A A A A A


No. blows per layer 60/60/60 53 53/53/53 73/73/73 53/53/53 70/70/70 53/53/53

Dry Density g/cm3 2.239 2.260 2.259 2.260 2.256 2.257 2.209

Density Ratio (LDR) % 99.1 100 100.0 100.0 99.8 99.9 97.7

Moisture Ratio (LMR) % 95.3 97 97.7 97.7 100.0 100.0 100.0

BR @ 2.5 mm (%) 133.8 148 156.9 184.1 151.3 134.7 104.3

BR @ 5.0 mm (%) 150.6 164 181.7 216.7 130.7 145.5 122.4

CBR (%) 150.6 164 181.7 216.7 130.7 145.5 122.4

Correction (mm) 0.61 NR 1.28 0.5 0.4 0.4 0.0

Swell (%) -0.1 0 -0.1 0.0 0.0 0.0 0.0

Moisture ww NR NR 8.7 8.6 NR 9.0 6.9

Moisture w30 8.7 8.8 8.6 8.5 8.6 9.1 9.2

Moisture wr 9.0 8.2 NR NR 9.0 8.7 NR


Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0-50kN 0-25kN 0-50kN 0-50kN


Calibration Class (AA, A, B, C etc) A A B A/B/C A A/AA A/AA/B/C

Hand driven (H) or motorised (M) M M M H M M M

Rate of penetration (mm/min) 0.99mm/min 0.99mm/min 1mm/min 1mm/min 1.0mm/min 0.98mm/min 0.94mm/min

Seating load applied (N) 4.5KG 4.5 50kN 50 200 197N 0.044kN



Graph computer or hand (C/H) C C C H C C C

Condition of material Moist Moist Good Moist OK Moist Moist

Loads in ( N or kN ) kN N kN N kN N kN

0 0.00 NR 0.005 0 -0.004 NR -0.001

0.5 1.006 4582 0.088 1130 2.426 1612 2.646

1 3.060 8743 0.676 5200 6.254 5338 5.464

1.5 6.177 12780 2.679 10100 10.235 9350 8.275

2 9.827 16278 6.458 15100 13.879 12831 11.135

2.5 13.511 19504 10.850 19900 17.651 15863 13.690

3 16.992 22543 15.158 24300 21.027 18622 16.100

3.5 20.143 25312 18.941 28380 24.028 21156 18.217

4 22.962 27729 22.317 32200 25.886 23309 20.469

4.5 25.207 29925 25.528 35650 NR 25372 22.365

5 27.331 32371 28.750 39500 NR 27406 24.169

6 31.416 37165 34.444 NR NR 31567 27.947

7.5 36.125 43200 NR NR NR 37499 33.116

8 37.442 45811 NR NR NR 39080 NR

10 41.960 NR NR NR NR 45333 42.28710.512.5 47.201 NR NR NR NR NR NR


Number 43 44 45 46 47 48 49





Code N5 Z3 P6 C4 Z9 Y3 Q5


Moisture Content Variation (Wv) (%) 0.1 0.3 0.1 -0.1 -0.9 0.1



No. blows per layer 53 45 53/53/53 52/52/52 NR 53/53/53

Dry Density g/cm3 2.259 2.268 2.259 2.260 2.455 2.256



BR @ 2.5 mm (%) 125.1 161.0 227.3 106.1 167.4 111.5

BR @ 5.0 mm (%) 173.0 199.7 NR 138.9 212.1 135.2

CBR (%) 173.0 199.7 NR 138.9 212.1 135.2

Correction (mm) 0.5 1.0 0.8 1.0 0.95 1.5

Swell (%) -0.1 -0.2 -0.3 -0.2 -0.1 0.0

Moisture ww 9.2 8.8 8.6 9.4 8.5 9.7

Moisture w30 8.8 8.7 8.6 8.6 8.2 8.9

Moisture wr 8.5 NR 8.6 8.6 7.9 8.8

Date last calibrated 08/2015 9/06/15 23/04/15 11/2015 11/2015 31/10/14

Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0-60kN 0-60kN 0-40kN

Load cell (C) or ring (R) R C C R R C

Calibration Class (AA, A, B, C etc) A A AA A A A

Hand driven (H) or motorised (M) M M M M M H

Rate of penetration (mm/min) 1mm/min 1.1mm/min 1mm/min 1.09mm/min 1.09mm/min 1mm/min

Seating load applied (N) 0.045kN Y 0.045kN 52N 52N 30N

Seating load set to zero (Y/N) N Corrected Y Y Y Y


Graph computer or hand (C/H) C C C H H C

Condition of material Good Satisfactory Moist Moist Moist Good

Loads in ( N or kN ) N N kN N N N

0 NR 0 0 0 1253 0

0.5 NR 1190 0.47 783 1253 395

1 NR 3040 3.32 2140 3184 1461

1.5 NR 5880 9.02 3967 6003 3210

2 NR 9550 15.0 6055 9500 5127

2.5 NR 13180 21.3 8509 13572 7389

3 NR 17000 26.9 11275 18009 9758

3.5 NR 21120 32.2 14123 NR 12450

4 NR 25500 36.9 16808 26987 14950

4.5 NR 29130 41.3 19679 NR 17370

5 NR 33000 45.6 22394 35026 20220

6 NR 40190 NR 27666 NR 25120

7.5 NR 49370 NR 34661 53348 30650

8 NR 52030 NR 36644 NR 32700

10 NR NR NR 45049 73654 3950010.512.5 NR NR NR NR 82267 NR


Number 50 51 52 53 54 55 56





Code T7 K4 V5 N4 T8 C2 E4


Moisture Content Variation (Wv) (%) 0.5 0.3 NR NR 0.2 0.0


Compaction Method - Standard (Y/N) Y Y Modified Modified Y Y

No. blows per layer 110/66/110 39/44/40 22 22 53/53/53 53/53/53

Dry Density g/cm3 2.271 2.262 2.268 2.271 2.264 2.277



BR @ 2.5 mm (%) 126.8 212.9 88.4 124.7 160 110

BR @ 5.0 mm (%) 162.3 252.4 126.1 161.1 180 130

CBR (%) 162.3 252.4 126.1 161.1 180 130

Correction (mm) 1.0 1.3 NR NR 1.0 0

Swell (%) -0.3 0 -0.02 -0.02 0.0 0.0

Moisture ww 9.2 9.1 9.0 9.19 9.3 2.5

Moisture w30 8.7 9.3 8.29 8.62 8.4 8.7

Moisture wr 8.4 8.2 8.40 8.49 8.5 8.4


Calibrated range (kN) 0-50kN 5-50kN 0-200kN 0-100kN 0-50kN 0-50000N

Load cell (C) or ring (R) C R C C R C

Calibration Class (AA, A, B, C etc) B/A A B B A A

Hand driven (H) or motorised (M) H H M M M M

Rate of penetration (mm/min) 1.0mm/min 1mm/min 1mm/min 1mm/min 1.0mm/min 1mm/min

Seating load applied (N) 250N 250N 250N 250N 0 200kN

Seating load set to zero (Y/N) Y Y Y Y N Y


Graph computer or hand (C/H) NR NR C C C C

Condition of material Satisfactory Moist Good Good Good Adequate

Loads in ( N or kN ) N N N N kN

0 0 0 0 0 0.00 NR

0.5 912 1745 260 334 0.89 NR

1 2350 4536 655 904 3.11 NR

1.5 4326 9337 1327 2070 6.13 NR

2 7028 10819 2462 4320 9.38 NR

2.5 9797 18557 4046 7380 13.88 NR

3 13137 22416 5940 10720 17.54 NR

3.5 16488 26200 8145 14240 21.14 NR

4 19650 29381 10560 17620 24.42 NR

4.5 22590 33241 NR NR 27.37 NR

5 25835 37961 15720 24040 30.32 NR

6 31935 49986 NR NR 36.10 NR

7.5 39825 NR 29200 38800 43.90 NR

8 42535 NR NR NR 46.31 NR

10 49898 NR 41080 52550 NR NR10.512.5 NR NR 51200 65200 NR NR


Number 57 58 59 60 61 62 63

Section 1 of 8


Note: Blank or NR = No result returned, Green are calculated/corrected results by PT coordinator.



Code M3 R6 E5 X7 S4 G2 R7






Dry Density g/cm3 2.249 2.264 2.263 2.260 2.262 2.255

Density Ratio (LDR) % 99.5 100.0 100.1 100 100.1 99.8

Moisture Ratio (LMR) % 96.6 98.0 98.6 99 90.7 95.3

BR @ 2.5 mm (%) 135.5 110 156.7 140 120.0 120.0

BR @ 5.0 mm (%) 180.8 150 189.9 170 140.0 140.0

CBR (%) 180.8 150 189.9 170 140.0 140.0

Correction (mm) 0.5 1.8 0.5 1.0 0.8 0

Swell (%) -0.2 -0.1 0.05 -0.2 -0.11 -0.31

Moisture ww NR 100.7 8.5 8.8 8.5 9.0

Moisture w30 8.2 8.1 8.7 8.6 8.8 9.2

Moisture wr 8.1 8.0 8.7 8.9 NR NR



Load cell (C) or ring (R) R NR C C C C

Calibration Class (AA, A, B, C etc) A A A NR A A


Rate of penetration (mm/min) 0.9mm/min 1mm/min 1mm/min 1mm/min 1.0mm/min 1.0mm/min

Seating load applied (N) 0 100N 250N 250N 150N 150N


Period Cured (hours) 46 48 >48 48 52 52

Graph computer or hand (C/H) C C C NR H H

Condition of material Moist Moist Moist Moist Good Good

Loads in ( N or kN ) kN N kN N N N

0 0.46 0 0.00 0 NR NR

0.5 1.71 440 1.72 770 698 2957

1 3.80 910 4.61 2450 2282 6283

1.5 6.68 1375 8.37 4870 4567 9490

2 10.35 2525 12.60 7790 7335 12587

2.5 14.16 4485 16.74 11090 10429 15677

3 17.88 6860 20.69 14550 13479 18546

3.5 21.36 9580 NR 18110 16550 21237

4 24.89 12470 28.05 21470 19422 23772

4.5 28.37 15480 NR 24620 22152 26138

5 31.81 18600 34.49 27550 24674 28256

6 39.19 25080 NR 33000 29729 32332

7.5 49.55 34400 NR 41150 36801 38520

8 52.94 37360 NR NR 38985 40378

10 65.06 48120 NR NR NR NR10.512.5 79.18 59650 NR NR NR NR


Number 64 65 66 67 68 69 70

Section 1 of 8







Moisture Content Variation (Wv) (%) 0.2 0.2 -0.2 NR 0.0 0.2 -0.1

Compaction (Manual or Auto) M M M M A M M


No. blows per layer 46/42/44 53/54/53 100/100/105 53/53/53 NR 112/117/110 48/48/50

Dry Density g/cm3 2.270 2.257 2.265 2.252 2.243 2.264 2.269



BR @ 2.5 mm (%) 155.4 109.1 154 116.5 129.3 110 133.9

BR @ 5.0 mm (%) 195.2 129.1 208 154.6 157.4 140 171.8

CBR (%) 195.2 129.1 208 154.6 157.4 140 171.8

Correction (mm) 1.2 0.5 0.5 1.8 0.4 4.1 0.0

Swell (%) -0.1 -0.1 0 -0.5 0.0 -0.3 0.0

Moisture ww 9.4 NR 9.1 9.2 8.7 10.1 9.5

Moisture w30 8.6 8.7 8.6 9.0 8.8 8.4 8.9

Moisture wr 8.4 8.3 NR 8.7 8.3 8.4 8.2

Date last calibrated 4/04/16 30/03/16 April 16 8/06/16 2/07/15 26/11/15 30/08/16

Calibrated range (kN) 0-50,000N 0-50kN 0-50kN 0-50kN 0-100kN 0.01-50kN 0-50kN


Calibration Class (AA, A, B, C etc) C NR A C AA/A A AA


Rate of penetration (mm/min) 1mm/min 1mm/min 1.00mm/min 1.02mm/mm 1mm/min 1.09mm/min 1.0mm/min

Seating load applied (N) 25N 250N 0.044kN 250N 4.5kg 0.240kN 35N


Period Cured (hours) 48 48+ 48 48 49 72 72


Condition of material Moist Good Dry Dry Good Good Moist

Loads in ( N or kN ) N N kN kN kN kN N

0 0 0 0.154 0 0 0.02 0.0

0.5 100 1273 2.241 0.086 1.0381 0.06 2998

1 813 3479 4.906 0.488 3.1426 0.06 6518

1.5 2801 6144 8.158 1.393 6.4154 0.12 10347

2 6349 8736 12.149 2.947 10.4782 0.25 14051

2.5 10491 11446 16.249 5.159 14.6381 0.34 17679

3 14635 14398 20.453 7.767 18.7945 0.51 21180

3.5 18643 16795 24.795 10.999 22 1.16 24798

4 22623 19292 29.057 13.699 26.9747 2.23 28172

4.5 26752 21860 33.172 16.632 31 3.77 31740

5 30179 23733 37.266 19.684 34.9003 5.77 34018

6 37209 27888 45.021 25.772 42 10.66 41448

7.5 45712 34241 55.331 34.872 53.6686 19.04 NR

8 48404 36632 NR 37.876 58 21.87 NR

10 NR 47124 NR 49.491 70.3965 32.57 NR10.512.5 NR NR NR NR 86.0589 44.72 NR


Number 1 2 3 4 5 6 7

6.0 Particpants Test Results - Sample B


D8 , Values provided above do not correspond to

penetration values shown here.








No. blows per layer 53/53/53 53/53/53 53/53/53 53/53/53 80/70/100 65/68/68 56

Dry Density g/cm3 2.297 2.253 2.260 2.265 2.261 2.258 2.257



BR @ 2.5 mm (%) 148.5 83.6 110 133.4 86.8 170 147.4

BR @ 5.0 mm (%) 186.9 112.0 150 171.1 131 220 155.5

CBR (%) 186.9 112.0 150 171.1 131 220 155.5

Correction (mm) 0.1 0.84 0.201 1.7 0 0.9 0.7

Swell (%) 0.0 -0.3 0.0 0.3 -0.2 0.0 0.0

Moisture ww 8.4 8.5 8.6 9.0 8.4 NR 9.5

Moisture w30 8.6 8.9 8.7 8.8 9.3 8.7 8.6

Moisture wr 8.4 8.8 8.5 8.6 8.2 8.5 8.7


Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0-50kN 0.2-40kN 0-50kN 0-50kN


Calibration Class (AA, A, B, C etc) A AA A/B/C A A A A

Hand driven (H) or motorised (M) M M M M H M H

Rate of penetration (mm/min) 1mm/min 1mm/min 1mm/min 1.0mm/min 1mm/min 1.0mm/min 1mm/min

Seating load applied (N) 247N 0.120 263 45N 0.25kN 250N 250kN




Condition of material Dry Good Moist Acceptable Good Sealed Moist

Loads in ( N or kN ) N kN kN N kN kN N

0 0 0.000 0 0 0 0.00 0

0.5 3367 0.668 2.06 254 1.2 1.17 976

1 7183 1.797 4.49 977 3.4 3.30 3468

1.5 11252 3.450 7.36 2444 5.9 6.31 7276

2 15150 5.336 10.40 4607 8.55 10.04 11168

2.5 19000 7.316 13.20 7157 11.46 14.51 14594

3 23041 9.471 16.40 9864 14.34 18.83 18624

3.5 26870 11.652 19.82 12902 17.22 23.37 20356

4 30341 14.015 23.08 16147 20.39 27.65 23042

4.5 33721 16.345 26.00 19463 23.07 31.75 25530

5 36888 18.519 28.90 22965 25.93 35.85 27938

6 42321 22.801 35.58 29370 31.62 44.10 32402

7.5 49841 29.534 42.30 35642 39.31 NR 38248

8 NR 31.610 44.49 41615 41.50 NR 40462

10 NR 39.464 NR 52066 NR NR NR10.512.5 NR 47.710 NR 62456 NR NR NR


Number 8 9 10 11 12 13 14

6.0 Particpants Test Results - Sample B 6.0 Particpants Test Results - Sample B









No. blows per layer 66/64/64 56/53/60 40/40/40 26/30/29 NR 53 52/52/52

Dry Density g/cm3 2.262 2.273 2.260 2.260 2.250 2.263 2.265



BR @ 2.5 mm (%) 103.3 159.1 113.6 180 166.8 154.4 55.0

BR @ 5.0 mm (%) 160.9 202.0 141.4 210 213.3 184.6 119.1

CBR (%) 160.9 202.0 141.4 210 213.3 184.6 119.1

Correction (mm) 0.50 0.6 0.358 1.6 0.9 0.5 0

Swell (%) 0.0 0.0 0.0 0.0 -0.4 0.0 -0.3

Moisture ww 9.3 9.1 9.1 8.5 9.2 8.5 9.3

Moisture w30 8.8 8.7 8.6 8.7 8.3 8.4 8.5

Moisture wr 8.6 8.5 8.4 NR 8.5 9.5 8.4

Date last calibrated 22/05/15 11/10/14 9/10/15 27/04/16 16/05/16 22/07/15 May 2016

Calibrated range (kN) 0-50kN 0-50kN 0-50kN 50kN 0.001-50kN 0-40kN 0-50kN

Load cell (C) or ring (R) C C C C C C. C

Calibration Class (AA, A, B, C etc) A/B A A A/B/C A A A

Hand driven (H) or motorised (M) M M M M M M. M

Rate of penetration (mm/min) 1.0mm/min 1.0mm/min 1.0mm/min 1mm/min 0.99mm/min 1.0mm/min 1.0mm/min

Seating load applied (N) 45N 0.25kN 0.25kN 20N 250N 0.250 NR


Period Cured (hours) 70.5 148 48 96 48 48 56

Graph computer or hand (C/H) C C C C C C. C

Condition of material Moist Good Good Sealed Sealed Good Good

Loads in ( N or kN ) N N N N N N kN

0 0 0 0 0 0.000 0.0 0

0.5 402 1450 1110 1148 2.689 2031 0.208

1 1634 4190 3410 2988 5.855 4788 1.043

1.5 3817 7990 6340 5468 9.677 8530 2.648

2 6644 12090 9610 8428 11.250 12600 4.625

2.5 9914 16570 12820 11480 14.111 16690 7.261

3 13639 20700 15720 14888 18.178 20380 10.255

3.5 17231 24840 NR 18520 22.575 24050 13.749

4 20923 28720 21420 22162 26.977 27490 16.978

4.5 24644 32640 NR 26228 31.448 30630 20.261

5 28357 36220 26410 30798 35.738 33640 23.590

6 35393 43250 NR 36948 43.481 39680 30.313

7.5 45226 NR 37850 49565 53.052 NR 38.694

8 NR NR NR NR 55.924 NR 41.304

10 NR NR NR 6222 67.028 NR 52.49710.5 9.512.5 NR NR NR NR 81.641 NR NR


Number 15 16 17 18 19 20 21





Code B8 S6 X8 T2 Y9 A2 X6 S4


Moisture Content Variation (Wv) (%) 0.0 0.1 NR 0.0 0.1 0.2 -0.1

Compaction (Manual or Auto) M M M M M M A


No. blows per layer 44/44/44 53/53/53 53/53/53 53/53/53 53/53/53 44/55/70 80/75/75

Dry Density g/cm3 2.270 2.250 2.207 2.262 2.258 2.256 2.261

Density Ratio (LDR) % 100.4 99.6 98 100.1 99.9 100 100.0


BR @ 2.5 mm (%) 140 100 NR 52.3 115.8 120.0 113.6

BR @ 5.0 mm (%) 180 130 150 88.3 150.0 150.0 151.5

CBR (%) 180 130 150 88.3 150.0 150.0 151.5

Correction (mm) 1.190 3.384 NR 0.0 1.5 0.5 0.7

Swell (%) 0.0 0.0 -2.5 0.0 -1.0 0.0 NR

Moisture ww 9.1 8.3 NR 111.7 8.8 9.7 8.6

Moisture w30 9.1 8.7 NR 101.0 8.7 8.7 8.6

Moisture wr 8.5 8.7 NR 95.8 8.0 8.6 8.6

Date last calibrated May 2015 3/06/16 25/05/15 6/01/15 1/03/15 June 2015 23/08/16

Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0 - 50,000N 0-50kN 0.045-50kN 0-50kN

Load cell (C) or ring (R) C R C C C C C

Calibration Class (AA, A, B, C etc) NR AA/B A A A/B/C A A/B


Rate of penetration (mm/min) 0.92 1.06 1 1.00mm/min 1mm/min 1mm/min 1.00mm/min

Seating load applied (N) 0.05kN 16 0.25kN 45 0 0.045 0

Seating load set to zero (Y/N) N N N Y N Y Y


Graph computer or hand (C/H) C C C C C H H

Condition of material OK Damp Damp Good Good Good Good

Loads in ( N or kN ) kN kN kN N kN kN ?

0 0.05 0.16 0.25 50 0.0 NR 0

0.5 0.67 0.60 1.20 236 0.20 0.260 960

1 2.19 1.32 2.78 770 0.89 1.700 2500

1.5 4.41 2.13 4.98 2540 2.18 4.000 4740

2 6.91 3.10 7.43 3980 4.13 7.40 7450

2.5 10.18 4.13 10.16 6910 6.50 11.100 10370

3 13.77 5.25 13.04 9070 9.14 15.00 13490

3.5 17.58 6.38 15.87 12390 11.94 18.600 16600

4 21.23 7.52 19.02 13420 15.00 22.800 19700

4.5 24.74 8.73 21.86 15560 17.94 23.800 22800

5 28.15 9.96 24.79 17490 20.96 27.000 25640

6 34.55 14.27 30.41 20820 26.67 33.100 31370

7.5 44.90 21.97 38.39 27210 34.82 41.600 39000

8 48.00 24.29 40.79 29340 NR 43.900 41440

10 NR 33.22 49.79 38160 46.87 NR 5068010.5 -76.1912.5 NR 43.02 NR 48680 NR NR 59000


Number 22 23 24 25 26 27 28







Moisture Content Variation (Wv) (%) 0.2 0.5 0.4 NR 0.1 0.0




Dry Density g/cm3 2.260 2.270 2.272 2.260 2.262 2.260



BR @ 2.5 mm (%) 155.3 195.0 170.2 152.9 50 140.9

BR @ 5.0 mm (%) 202.0 229.7 216.6 190.1 60 167.8

CBR (%) 202.0 229.7 216.6 190.1 60 167.8

Correction (mm) 0.5 0.5 0.3 1.1 0.0 0.5

Swell (%) 0.1 0.0 -0.02 0.07 0.0 0.0

Moisture ww NR 8.9 9.4 8.9 9.8 NR

Moisture w30 8.2 8.3 8.6 9.4 9.5 8.7

Moisture wr NR 8.3 8.2 8.9 9.3 8.4


Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0-50kN 0-50kN 0.2-50kN


Calibration Class (AA, A, B, C etc) A/B A AA A/B/C A A/B/C

Hand driven (H) or motorised (M) M M M H M M

Rate of penetration (mm/min) 1mm/min 1.0mm/min 1.0mm/min 1mm/min 1mm/min 1mm/min

Seating load applied (N) 0.25kN 50N 45N 0.04 0.1kN 50N

Seating load set to zero (Y/N) Y N Y N Y Y


Graph computer or hand (C/H) H C C C C C

Condition of material Good Moist Suitable Good Moist NR

Loads in ( N or kN ) kN kN N kN N N

0 0.0 0.00 0 NR 0 0.000

0.5 1.64 0.74 2032 0.34 1958 1539

1 3.74 2.92 6108 1.38 2948 4026

1.5 7.89 7.21 11005 3.69 3980 7405

2 12.16 12.26 15636 7.34 5086 11190

2.5 16.13 17.69 20184 11.42 6279 15091

3 20.50 22.47 24637 15.57 7563 18596

3.5 24.55 27.09 28965 19.42 8817 21783

4 28.45 31.26 33196 23.07 10121 24883

4.5 32.15 35.68 37198 27.05 11402 27731

5 36.05 39.71 41026 30.47 12788 30138

6 43.89 47.32 48023 37.08 15453 35968

7.5 50.00 NR NR NR 19109 44147

8 NR NR NR NR 20339 46897

10 NR NR NR NR 25585 NR10.512.5 NR NR NR NR 31609 NR


Number 29 30 31 32 33 34 35








Compaction (Manual or Auto) M M M M M A


No. blows per layer 53/53/53 50 53/53/53 53/53/53 53/53/53 53/53/50

Dry Density g/cm3 2.260 2.260 2.262 2.261 2.260 2.264


Moisture Ratio (LMR) % 100 100.0 98.8 100.0 100.0 97.7

BR @ 2.5 mm (%) NR 130.0 120.6 103.4 124.8 136.2

BR @ 5.0 mm (%) 120 160.0 126.5 126.1 NR NR

CBR (%) 120 160.0 126.5 126.1 NR NR

Correction (mm) 0.4 0.4 0.0 0.60 0.16 0.8

Swell (%) 0.0 0.0 0.0 0.0 0.0 0.0

Moisture ww 9.4 9.3 NR NR NR 8.4

Moisture w30 8.7 9.1 8.9 8.9 8.7 8.6

Moisture wr 8.6 8.3 8.7 8.8 8.8 8.4


Calibrated range (kN) 100kN 0-50kN 0.2-250kN 0-250kN 0.2-250kN 0-25kN


Calibration Class (AA, A, B, C etc) A AA A/AA C-AA A/AA AA


Rate of penetration (mm/min) 1mm/min 1.0mm/min 1mm/min 0.99mm/min 1mm/min 1mm/min

Seating load applied (N) 250N 0.250 250N 200N 250N 40N


Period Cured (hours) 48-50 48 72 72 72 50

Graph computer or hand (C/H) C NR C C C C

Condition of material Dry Sealed Moist Moist Moist Good

Loads in ( N or kN ) N kN kN kN kN kN

0 5.765 0 -0.007 -0.001 -0.001 0.001

0.5 1148.7 1.402 4.654 0.814 1.487 0.228

1 3364.7 3.948 7.881 2.421 5.405 1.726

1.5 6008.6 7.438 10.821 4.772 8.988 4.892

2 8638.7 10.722 13.431 7.498 12.406 8.772

2.5 11347.1 13.998 15.923 10.390 15.562 12.607

3 13805.7 17.398 18.092 13.131 18.697 15.914

3.5 16045.1 20.430 20.203 15.769 21.800 18.968

4 18008.9 23.505 22.228 18.493 24.642 21.815

4.5 20007.3 26.577 24.299 21.195 25.049 24.365

5 22053.4 29.670 25.038 23.824 NR 24.735

6 25867.2 35.097 NR 24.974 NR NR

7.5 31000.9 42.835 NR NR NR NR

8 32712.8 45.388 NR NR NR NR

10 38428.1 NR NR NR NR NR10.512.5 45434.5 NR NR NR NR NR


Number 36 37 38 39 40 41 42








Moisture Content Variation (Wv) (%) -0.2 -0.2 0.2 0.2 0.0 -0.2 0.1

Compaction (Manual or Auto) A A A A A A A


No. blows per layer 65/65/65 53 53/53/53 73/73/73 53/53/53 70/0/70 71/71/71

Dry Density g/cm3 2.253 2.262 2.260 2.270 2.264 2.255 2.260

Density Ratio (LDR) % 99.7 100 100 100.4 100.2 99.8 100.0

Moisture Ratio (LMR) % 97.7 98 97.7 97.7 100.0 102.3 98.8

BR @ 2.5 mm (%) 173.5 168 202.1 174.2 134.7 154.9 156.3

BR @ 5.0 mm (%) 203.8 188 229.7 218.2 160.0 176.2 196.0

CBR (%) 203.8 188 229.7 218.2 160.0 176.2 196.0

Correction (mm) 0.0 NR 0.32 0.6 0.23 0.3 0.6

Swell (%) 0.0 0 -0.2 0.0 0.0 0.0 0.0

Moisture ww NR NR 8.4 8.4 NR 8.9 8.5

Moisture w30 8.5 8.8 8.4 8.7 8.7 8.8 8.9

Moisture wr 8.5 8.5 NR NR 8.9 8.7 NR


Calibrated range (kN) 0-50kN 0-50kN 0-50kN 0-50kN 0-25kN 0-50kN 0-50kN


Calibration Class (AA, A, B, C etc) A A B A/B/C A A/AA AA/A/B/C

Hand driven (H) or motorised (M) M M M H M M M

Rate of penetration (mm/min) 0.99mm/min 0.99mm/min 1mm/min 1mm/min 1.0mm/min 0.99mm/min 0.85mm/min

Seating load applied (N) 4.5KG 4.5 50kN 50 200 228N 0.234kN



Graph computer or hand (C/H) C C C H C C C

Condition of material Moist Moist Good Moist OK Moist Moist

Loads in ( N or kN ) kN N kN N kN N kN

0 0.00 0.062 -0.001 0 0.026 NR -0.003

0.5 3.739 6332 2.520 1210 1.654 1918 1.389

1 8.676 10922 7.368 4430 4.861 5750 3.801

1.5 13.897 14938 12.931 8800 8.653 10127 7.341

2 18.639 18669 17.954 13200 12.399 14325 11.372

2.5 22.574 22168 23.398 17800 16.181 18234 15.631

3 26.505 25315 28.214 22400 19.534 21560 19.810

3.5 30.191 28341 32.187 27000 22.728 24583 23.657

4 33.752 31333 35.947 31050 25.615 27298 27.317

4.5 36.951 34417 39.729 35000 28.179 30121 31.365

5 40.149 37098 43.359 39200 30.645 33052 34.814

6 45.917 42407 NR 46500 31.674 38258 41.581

7.5 NR 49342 NR NR NR 46113 NR

8 NR NR NR NR NR 48055 NR

10 NR NR NR NR NR NR NR10.512.5 NR NR NR NR NR NR NR


Number 43 44 45 46 47 48 49

Section 1 of 8







Moisture Content Variation (Wv) (%) -0.1 0.3 0.1 0.3 -0.7 0.1


Compaction Method - Standard (Y/N) Y Y Y Y Y3 Y

No. blows per layer 53 40 53/53/53 52/52/52 NR 53/53/53

Dry Density g/cm3 2.255 2.266 2.260 2.266 2.280 2.266



BR @ 2.5 mm (%) 116.3 143.6 185.6 128.8 173.5 121.4

BR @ 5.0 mm (%) 170.6 186.4 226.3 170.7 218.7 143.8

CBR (%) 170.6 186.4 226.3 170.7 218.7 143.8

Correction (mm) 0.5 0.8 0.85 0.75 0.95 0.9

Swell (%) -0.1 -0.1 -0.1 0 -0.1 -0.1

Moisture ww 9.4 9.0 9.3 9.6 8.8 9.5

Moisture w30 8.9 8.5 8.7 8.4 8.2 9.0

Moisture wr 8.6 NR 8.6 8.2 7.9 8.7

Date last calibrated 08/2015 9/06/15 23/04/15 11/2015 11/2015 31/10/14


Load cell (C) or ring (R) R C C R R C

Calibration Class (AA, A, B, C etc) A A AA A A A

Hand driven (H) or motorised (M) M M M M M H

Rate of penetration (mm/min) 1mm/min 1.1mm/min 1mm/min 1.09/min 1.09mm/min 1mm/min

Seating load applied (N) 0.045kN Y 0.045kN 52N 52N 30N

Seating load set to zero (Y/N) N Corrected Y Y Y Y


Graph computer or hand (C/H) C C C H H C

Condition of material Good Satisfactory Moist Moist Moist Good

Loads in ( N or kN ) N N kN N N N

0 NR 0 0 0 0 0

0.5 NR 1070 0.33 835 887 989

1 NR 2940 2.21 2767 2558 3055

1.5 NR 5820 6.41 5377 5377 5421

2 NR 9220 11.3 8456 9292 8259

2.5 NR 12920 16.5 11849 13990 11940

3 NR 16690 21.6 15295 18949 13890

3.5 NR 20440 26.4 18814 NR 16710

4 NR 24220 30.8 22028 28136 19280

4.5 NR 28180 35.0 25718 NR 21880

5 NR 31790 38.9 29128 36540 24190

6 NR 38420 46.0 35994 NR 29060

7.5 NR 47810 NR 44840 54706 35250

8 NR 51000 NR 48168 NR 37280

10 NR NR NR 59143 75046 4060010.512.5 NR NR NR NR 81954 NR


Number 50 51 52 53 54 55 56

Notes: (1) NR = No result returned

Section 1 of 8






Moisture Content Variation (Wv) (%) 0.1 -0.1 NR NR 0.2 0.0


Compaction Method - Standard (Y/N) Y Y N Modified Y Y

No. blows per layer 99/88/121 50/51/48 22 22 53/53/53 53/53/53

Dry Density g/cm3 2.249 2.252 2.266 2.271 2.264 2.277

Density Ratio (LDR) % 99.5 100.1 100.3 100.5 100.2 101

Moisture Ratio (LMR) % 98.8 98.8 96.11 96.01 97.7 100

BR @ 2.5 mm (%) 164.7 258.1 119.3 119.7 140 110

BR @ 5.0 mm (%) 204.9 236.1 157.9 157.5 170 130

CBR (%) 204.9 258.1 157.9 157.5 170 130

Correction (mm) 0.9 1.5 NR NR 1.2 0

Swell (%) 0.1 -0.2 -0.01 -0.27 0.0 -1.0

Moisture ww 9.5 9.3 9.0 8.88 9.3 2.5

Moisture w30 8.4 9.3 8.49 8.19 8.6 8.6

Moisture wr 8.2 8.5 8.12 8.07 8.5 8.4


Calibrated range (kN) 0-50kN 5-50kN 0-100kN 0-100kN 0-50kN 0-50000N

Load cell (C) or ring (R) C R C C R C

Calibration Class (AA, A, B, C etc) B/A A B B A A

Hand driven (H) or motorised (M) H H M M M M

Rate of penetration (mm/min) 1mm/min 1mm/min 1mm/min 1mm/min 1.0mm/min 1mm/min

Seating load applied (N) 250N 250N 250N 250N 0 200kN

Seating load set to zero (Y/N) Y Y Y Y N Y


Graph computer or hand (C/H) NR NR C C C C

Condition of material Satisfactory Moist Good Good Good Adequate

Loads in ( N or kN ) N N N N kN

0 0 0 0 0 0.00 NR

0.5 1228 2756 332 332 0.58 NR

1 3770 6059 876 868 2.26 NR

1.5 7225 9752 1799 1787 4.76 NR

2 11043 13297 3340 3234 7.68 NR

2.5 14998 17030 5425 5290 10.55 NR

3 18930 22279 8000 7735 14.74 NR

3.5 22515 30037 10960 10480 17.68 NR

4 26130 33787 14150 13670 20.70 NR

4.5 30710 36042 NR NR 23.69 NR

5 34444 38235 20660 19990 26.63 NR

6 41730 46766 NR NR 31.79 NR

7.5 NR NR 35840 35220 39.06 NR

8 NR NR NR NR 41.37 NR

10 NR NR 48680 48960 NR NR10.512.5 NR NR 60100 60600 NR NR


Number 57 58 59 60 61 62 63

Section 1 of 8







Moisture Content Variation (Wv) (%) 0.3 0.3 0.2 0 0.7 0.2




Dry Density g/cm3 2.261 2.263 2.256 2.260 2.266 2.237

Density Ratio (LDR) % 100.0 100.0 99.8 100 100.3 99.0

Moisture Ratio (LMR) % 96.8 96.3 102.5 100 91.9 97.7

BR @ 2.5 mm (%) 181.8 120 118.6 140 110 130.0

BR @ 5.0 mm (%) 198.0 160 151.5 180 140 160.0

CBR (%) 198.0 160 151.5 180 140 160.0

Correction (mm) 0.7 1.4 1.3 1.25 0.8 0.4

Swell (%) -0.2 -0.0 -0.1 -0.2 -0.16 -0.06

Moisture ww NR 101.4 8.8 8.9 8.5 8.8

Moisture w30 8.4 9.1 8.6 8.5 9.1 9.1

Moisture wr 8.3 7.7 8.6 9.4 NR NR



Load cell (C) or ring (R) R NR C C C C

Calibration Class (AA, A, B, C etc) A A A NR A A


Rate of penetration (mm/min) 0.9mm/min 1mm/min 1mm/min 1mm/min 1.0mm/min 1.0mm/min

Seating load applied (N) 0 100N 250N 250N 150N 150N


Period Cured (hours) 46 48 >48 48 52 52

Graph computer or hand (C/H) C C C NR H H

Condition of material Moist Moist Moist Moist Good Good

Loads in ( N or kN ) kN N kN N N N

0 0.46 0 0.00 0 NR NR

0.5 1.62 560 0.33 490 703 1601

1 3.57 1060 1.18 1550 2569 4369

1.5 6.50 1760 2.78 3320 4273 7407

2 9.89 3775 4.93 5830 6746 10620

2.5 13.88 6600 7.66 8800 9523 14022

3 17.83 9845 10.65 12320 12401 17325

3.5 21.87 13060 NR 16080 15287 20948

4 26.33 16490 16.97 19820 17771 23772

4.5 30.14 19650 NR 23320 20453 26490

5 33.57 22760 22.83 26710 22822 29226

6 40.77 29020 NR 32890 27853 34549

7.5 50.43 37540 35.79 42230 35328 42166

8 53.59 40160 NR 45000 37368 44432

10 65.34 49040 45.01 NR NR NR10.512.5 NR 58350 NR NR NR NR


Number 64 65 66 67 68 69 70

Section 1 of 8





67 App A CBR PT Instructions.docx

LabSmart Services

Proficiency Testing Program

California Bearing Ratio – 2016 (67)

INSTRUCTIONS FOR TESTER

1. Please check that the package you have received contains the following:

Instructions (for tester) Results Log Approximately 14.8 kg of soil sealed in a plastic bag labelled ‘2016 (67) CBR Sample’

Contact LabSmart Services if the bags are damaged or any item is missing.

2. When can I start testing? As soon as you have read these instructions carefully and

your supervisor has indicated that you may do so.

3. How long do I have to do the testing? You need to have the results back to LabSmart Services by the 12 October 2016.

4. Due to the possibility of segregation during transportation mix the sample thoroughly

prior to testing.

5. Split the sample into two equal portions, Sample A and Sample B. Keep in a sealed container.

6. There is no oversize material present in this sample. 7. You do not need to be accredited for AS 1289 6.1.1 (2014). You may use other

equivalent methods but it is preferable that AS 1289 6.1.1 (2014) be used.

8. Conduct the CBR test to AS 1289 6.1.1 (2014) using the following information.

Use an OMC of 8.6 %.

Adjust the moisture of the sample as per the test method mixing thoroughly at

intervals and cure for at least 48 hours. This should be done in a plastic bag

with the end tied/folded over.

As per clause 6(c) of the test method just prior to compaction take a sample to

determine final moisture content (w1) has been achieved i.e. OMC ± 0.5%.

Sample to be remoulded at 100% standard compaction.

Use a MDD of 2.260 t/m3

LDR be within 100 ± 1%

Apply a 4.5 kg surcharge.

Soak the sample as per the method for 4 days.

Swell is to be determined.

CBR is > 30 %

Take additional load readings at 3.5, 4.5, 6.0 and 8.0 mm penetration.

9. Repeat the test as per step 7 to obtain two sets of results. The same person should complete both tests.

Page 1 of 2

Appendix A



67 App A CBR PT Instructions.docx

10. Please study the “Results Log” carefully before beginning the test.

11. Record the results on the enclosed “Results Log”. Report each result according to the

log sheet. This will be different to the test method.

12. The Laboratory Manager or person responsible for checking must sign the log sheet to indicate that it has been checked.

13. Please retain any unused sample until the final report has been issued.

14. Have a query? Contact Peter Young at LabSmart Services. Phone. 0432 767 706

15. Fax or e-mail the “Result Log” to LabSmart Services by 12 October 2016.

Fax: (03) 8888 4987 OR

E-mail: [email protected]

16. Please retain the completed “Results Log” as this contains your confidential

participation code. You will need this code to identify your results in the technical report covering the proficiency testing program. It is also recommended that a copy of completed worksheets be kept with the results log in your proficiency file.

17. Proficiency testing can also form part of a laboratories training records for the technician who performed the test.

Thank you for participating in this proficiency testing program.

Page 2 of 2



67 App B CBR PT Results Log.docx

LabSmart Services

Proficiency Testing Program - California Bearing Ratio – 2016 (67)

RESULTS LOG for xxxx

Participation Code: xx

Please fax or e-mail the completed results log by 12 October 2016

E-mail: [email protected] or Fax: (03) 8888 4987

1. Please follow the instructions carefully. The test is to be performed twice and the

results entered into sections 3 and 4 below.

2. Please describe the characteristics of the CBR machine used for the tests:

Date last calibrated

Calibrated range (I.e.0-50 kN)

Load Cell or Load Ring?

Calibration (Class A, B, C?)

Hand driven or motorised platform?

Rate of penetration?

Please complete the following regarding the performance of the test

Condition of material as received

Seating load used

Has the seating load been set to zero? (Y/N)

Period cured for? (hours)

3. Please attach a copy of the CBR graph for each test. 4. COMMENTS: (Please ensure all 6 sections are completed)

…………………………………………………………………………………………………………………………………………………………………………………………………………………… …………………………………………………………………………………………………………

------------------------------------ ---------------------------------- --------------- Supervisor Name (Please Print) Signature Date

In signing the above, I acknowledge that the above results are approved and have been checked. I will also ensure that the results are kept confidential both internal and external to the laboratory until the issue of the final technical report covering this program.

Thank you for participating. Please retain these sheets for your records.

________________________________________________________________________

Have a query? Contact Peter on 0432 767 706. Page 1 of 3

Appendix B



mailto:[email protected]


5.

SAMPLE A Report

To Result

Test Method Used

Tested by: Name

Moisture (Clause 6[c]) (W1) (before compaction)

0.1 %

Moisture content variation (Wv) 0.1 %

Compaction Manual or Auto

Compaction Method Standard (Y/N)

Number of blows used per layer Number

Before Soaking

Dry density 0.001 g/cm3

Density Ratio (LDR)

0.1 %

Moisture Ratio (LMR)

0.1 %

BR @ 2.5 mm 0.1 %

BR @ 5.0 mm 0.1 %

Correction# 0.1 mm

Swell 0.1 %

After soaking

Moisture ww 0.1 %

Moisture w30 0.1 %

Moisture wr 0.1 %

# Enter zero if no correction is performed.

Please record the penetration/ load readings below (cross out and change if other

penetration values are used) OR attach worksheet for with penetration/load readings.

Penetration (mm)

Load (N)

Penetration

(mm) Load (N)

0 4.0

0.5 4.5

1.0 5.0

1.5 6.0

2.0 7.5

2.5 8.0

3.0 10.0

3.5 12.5

Page 2 of 3




6.

SAMPLE B Report

To Result

Test Method Used

Tested by: Name

Moisture (Clause 6[c]) (W1) (before compaction)

0.1 %

Moisture content variation (Wv) 0.1 %

Compaction Manual or Auto

Compaction Method Standard (Y/N)

Number of blows used per layer Number

Before Soaking

Dry density 0.001 g/cm3

Density Ratio (LDR)

0.1 %

Moisture Ratio (LMR)

0.1 %

BR @ 2.5 mm 0.1 %

BR @ 5.0 mm 0.1 %

Correction# 0.1 mm

Swell 0.1 %

After soaking

Moisture ww 0.1 %

Moisture w30 0.1 %

Moisture wr 0.1 %

# Enter zero if no correction is performed.

Please record the penetration/ load readings below (cross out and change if other

penetration values are used) OR attach worksheet for with penetration/load readings.

Penetration (mm)

Load (N)

Penetration

(mm) Load (N)

0 4.0

0.5 4.5

1.0 5.0

1.5 6.0

2.0 7.5

2.5 8.0

3.0 10.0

3.5 12.5

Page 3 of 3



Calculate correction line from: Correction = 0.46 mm

Lower = 1.0 mm 118.2 % Unrounded CBR = 142.4 %

Upper = 3.0 mm 142.4 % CBR = 140.0 %CBR @ 5.0 mm =

CBR @ 2.5 mm =

y = 31.061x4 - 496.95x3 + 2435.6x2 + 1645x - 108.3R² = 0.9999

0

2,000

4,000

6,000

8,000

10,000

12,000

14,000

16,000

18,000

20,000

22,000

24,000

26,000

28,000

30,000

32,000

34,000

36,000

38,000

40,000

0 1 2 3 4 5 6 7 8 9 10 11 12

Ap

plie

d L

oad

(N

)

Penetration (mm)

CBR Graph for Participant D9B

Data Values

Poly. (Data Values)

Correction



User

Typewritten Text

Appendix C - Graph Example

User

Typewritten Text

Documents

CBR - 2016 (67) PROFICIENCY TESTING PROGRAM REPORT · Report This report is available on the LabSmart Services website. The issue of this proficiency report was ... CBR Proficiency