Topic 1 Site Investigation PDF

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SITE ENGINEERING

DIPLOMA KEJURUTERAAN AWAM PKK


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C5306 SITE ENGINEERING

1. SITE INVESTIGATION (7 hours)

2. INTRODUCTION TO FOUNDATION (2 hours)

3. BEARING CAPACITY AD DESIGN OF SHALLOW

FOUNDATION (5 hours)

4. DEEP FOUNDATION (11 hours)

5. SETTLEMENT (5 HOURS)


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Evaluation

Continuous Assessment (CA) (50%)

Quiz - 5 (20%)

Assigment/Tutorial4 (30%)

Test3 (50%)

Final Examination (FE) (50%)


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SITE INVESTIGATION

TOPIC 1


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Course content

UNDERSTAND THE OBJECTIVES AND WORK

PROCEDURE IN SITE INVESTIGATION.

DEFINE SITE INVESTIGATION

STATE OBJECTIVE OF SITE INVESTIGATION

BASED ON BS5930 (1981)

EXPLAIN BRIEFLY THE WORK PROCEDURE INSITE INVESTIGATION


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Course content

UNDERSTAND PROSEDURE OF PRELIMINARY

WORK IN SITE INVESTIGATION

UNDERSTAND PROGRAMMED PLANNING

AND SCOPE OF SITE INVESTIGION

UNDERSTAND FIELD TEST

UNDERSTAND THE CRITERIA IN DETERMININGNUMBER AND TYPES OF SAMPLES

EXPLAIN TYPE OF SAMPLES


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Course content

UNDERSTAND THE CONTENT OF SITE

INVESTIGATION REPORT

USE THE GIVEN CONCEPT IN PERFORMING

PRELIMINARY ON-SITE SURVEY


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Define site investigationMJ TOMLINSON (2001) FOUNDATION DESIGN AND CONSTRUCTION

A site investigation in one form or another

is always required for any engineering or

building structure.

The investigation may range in scope from

a simple examination of the surface soils with or

without a few shallow trial pits, to a detailed

study of the soil and ground water condition to

a considerable depth below the surface by

means of boreholes and in-situ and laboratory

test on the materials encountered.


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SOIL INVESTIGATION

In the evaluation of an area for construction of

buildings or other structures, or as a source of

construction material, the soil condition must

be investigated before any detailed design are

made.

A soil investigation involves field sampling


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SOIL INVESTIGATION

A soil investigation involves

1. field sampling and testing

2. Laboratory analysis3. And preparation of report

The planning and evaluation of field work are

aided by a knowledge of the mechanics of soildeposits formation

Harold N. Atkins. Highway Materials, Soils, and Concretes (Fourth Edition). (2003)


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FIELD INVESTIGATIONTECHNIQUES

Soil investigation are conducted for most

medium to large sized building, highways,

bridges, dams, water control facilities,

harbors, and other structures.

The purpose is to find the allowable bearing

capacity for foundations, water resources, find

aggregate deposits, estimate infiltration andseepage rates, and to help assess land use

capabilities.


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The purposes of subsoil exploration(BRAJA M.DAS (2010) PRINSIPLES OF GEOTECHNICAL ENGINEERING)

1) Determining the nature of soil at the site and

its stratification

2) Obtaining disturbed and undisturbed soilsamples for visual identification and

appropriate laboratory tests.

3) Determining the depth and nature ofbedrock, if and when encountered


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4) Performing some in situ field test, such as

permeability test, vane shear test and SPT

5) Observing drainage condition from and into

the site

6) Assessing any special construction problem

with respect to the existing structure nearby

7) Determining the position of the water table

The purposes of subsoil exploration(BRAJA M.DAS (2010) PRINSIPLES OF GEOTECHNICAL ENGINEERING)


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Objective of site investigationbased on BS5930 (1981)

1. Suitability. To assess the general suitability of

the site and environs for the proposed works

including, where applicable, the implications

of any previous use or contamination of thesite. (Kesesuaian)

2. Design. To enable an adequate and economic

design to be prepared, including the design oftemporary works. (Rekabentuk)

f


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3. Construction. To plan the best method of

construction; to predict and provide against

difficulties and delays that may arise during

construction due to ground, groundwater andother local conditions; in appropriate cases,

to explore sources of local materials for use in

construction and to select sites for thedisposal of waste or extra materials.


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Obj i f i i i i


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6. Existing works. Unless the contrary can be

demonstrated, it should be assumed that site

investigations are necessary in reporting

upon the existing works and for investigatingcases where failure has occurred.


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Procedure in site investigation

Preliminary study/Desk study

Site survey

Programmed planning and scope of site investigation

Soil investigation and soil sampling

Laboratory testing

Report preparation of site investigation

Designing

Re-investigation research during construction and supervision


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DESK STUDY

This involves collecting as much information

as possible about the sit.

Sources includei. Geological maps

ii. Survey map


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DESK STUDY

Sources includei. Geological maps

ii. Topography

iii. Surface water & groundwateriv. Survey map

v. Aerial photographs

vi. Mining records

vii. Previous site investigation for the site or

adjacent site


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DESK STUDY


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SITE SURVEY

what is needed in light of existing information,

provide specific rationale for the scope and

methods of site investigation to make it

possible for reviewers to assess the adequacyof the investigation.

Describe what was carried out.

Show location of test holes or pits or

geophysical lines if any. Include field

observations at the site, soils and existing

conditions.


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Programmed planning andscope of site investigation

After a site survey carried out, engineers

(consultants) will design and scope of site

investigation program.

At this stage, engineers will determine

whether the data required by the designer.

The engineers next will choose the test-site

(in-situ test) and laboratory data to meet the

structural design for buildings, especially the

basic types (type of foundation: shallow or

deep foundation)


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SOIL INVESTIGATION ANDSOIL SAMPLING

Detailed investigation of the geological

processes and the soil conditions beneath the

surface of the hole by trial (trial pits), a bore

hole (boreholes) and others.

Survey of ground water also, examining the

damage to the nearby (e.g. deposition,

structure and process of sampling locations).to determine in detail the geological structure

of land including the thickness and type of

soil.


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SOIL INVESTIGATION ANDSOIL SAMPLING

Investigation should be conducted to prove

the validity of and expand the information

collected earlier.

As a whole, information about land needed in

order to determine the most suitable project,

providing design and carry out the

construction. For example, in constructionwork, when excavation work is carried, the

knowledge of the bottom layer and the water

in the soil needed for the following purposes:


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Three steps of soil exploration

BORINGDrilling or advancing a hole in the

ground

SAMPLING Removing soil from the hole

TESTING Determining characteristics orproperties of the soil


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LABORATORY TESTING

A preliminary examination of the nature and type

of soil brought to the laboratory is very

essential before deciding upon the type and

number of laboratory tests. Normally the SPT samples are used for this

purpose. First the SPT samples should be

arranged bore wise and depth wise. Each of thesamples should be examined visually. A chart

should be made giving the bore hole numbers

and the types of tests to be conducted on each

sample depth wise.


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LABORATORY TESTING

An experienced geotechnical engineer can do this

job with diligence and care. Once the types of

tests are decided, the laboratory assistant should

carry out the tests with all the care required foreach of the tests.

The test results should next be set out on a

suitable format bore wise and the soil is classifiedaccording to standard practice. The geotechnical

consultant should examine each of the tests

before being set out. Unreliable test results

should be discarded.


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1. Grain size distribution - Mechanical analysis

2. Liquid limit (LL)

3. Plastic limit (PL)

4. Specific gravity

5. Natural water content

6. Shear strength unconfined compression

- direct shear- Triaxial

LABORATORY TESTING


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7. Compressibility consolidation

8. Permeability

9. Compaction standard proctor & moditied

proctor10. CBR

11. Shear strength (soft clay) vane shear

12. Penetration test

LABORATORY TESTING

L b t t t l t d t il


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Laboratory test related to soilsinvestigation

TEST SAMPLE REQUIRED SOILSDISTURBED ORUNDISTURBED

UNDISTURBED COHESIVE GRANULAR

Moisture content X X X

Grain size X X X

Atterberg limits X X

Relative density (G.S) X X X

Density (unit weight) X X X

Unconfined compression X X

Triaxial compression X X X

Direct shear X X X

Consolidation X X

Vane shear X x

permeability x X

REPORT PREPARATION OF


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REPORT PREPARATION OFSITE INVESTIGATION

A report is the final document of the whole exercise

of soil exploration.

A report should be comprehensive, clear and to the

point. A report writer should be knowledgeable, practical

and pragmatic.

No theory, books or codes of practice provide all the

materials required to produce a good report. It is the

experience of a number of years of dedicated service

in the field which helps a geotechnical consultant

make report writing an art.


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SITE INVESTIGATION

A good report should normally comprise the following:

1) A general description ofthe nature of the project and

its importance.

2) A general description of the topographical featuresand hydraulic conditions of the site.

3) A brief descriptionofthe various field and laboratory

tests carried out.

4) Analysis and discussion of the test results



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REPORT PREPARATION OFSITE INVESTIGATION

5) Recommendations

6) Calculations for determining safe bearing

pressures, pile loads, etc.

7) Tables containing bore logs, and other field

and laboratory test results

8) Drawings which include an index plan, a site-

plan, test results plotted in the form ofcharts and graphs, soil profiles, etc.


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DESIGNING

The design of the building structure can be made by the

engineers.

The first structure to be designed is a basic building. Withreference to the design load (structure plan), the limit soil

deposition and soil type, foundation engineers will analyze

and determine the appropriate type of foundation in the

study area either in a shallow foundation or base.


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DESIGNING

If a soil layer is far from the ground, the basic choice

(pile foundation) should be considered. To determine

the basis of size or depth, the soil unit weight,

cohesion and friction angle of soil should be

obtained through the site investigation report.

RE INVESTIGATION RESEARCH DURING


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RE-INVESTIGATION RESEARCH DURINGCONSTRUCTION AND SUPERVISION

Sometimes there are

problems faced by the

contractors during the

construction being carried

out as an example of damageto piles during installation.

thus, a review of the basic

structure of the building

must be done to design thepile foundation is involved

again.


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Discussion

Site investigation should be split up into three

section;

1. A walk-over survey

2. An initial desktop study

3. Field investigations using trial pits

or boreholes

Discuss in group WHAT information should be

collect in a walk-over survey.


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Discussion

Describe site investigation?

What information usually required in soils

investigations includes?

Describe the technique sampling during soil

investigation?


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ASSIGNMENT 1GROUP TOPIC

1 Explain boring borehole methoda. Hand Auger

b. Rotary drilling

c. Hammer drilling

d. Wash boring

e. Core drilling

2 Explain field test carried out on site

Standard Penetration Test (SPT)


Cone Penetration Test (CPT)


Plate Load Test


Trial Test


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ASSIGNMENT 1GROUP TOPIC

6 Explain methods of observation and measurement of groundwater, methods of measuring water pressure

Vertical pipe

Piezometer

7 Explain types of sampler

Thin walled sampler Open drive sampler

Separate drum sampler/split spoon sampler

8 Explain types of sampler

Stationary piston sampler

Continuous sampler

Compressed air sampler

PROSEDURE OF


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PROSEDURE OFPRELIMINARY WORK

1. Lists important information for compilation

2. Identify necessary equipment for site

investigation exercise

3. Explain important points carried out during

programmed planning and scope of site

investigation

INFORMATION REQUIRED IN


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INFORMATION REQUIRED INSOIL INVESTIGATION

Depth, thickness and properties of each soil

layer

Location of groundwater table

Depth to bedrock

EQUIPMENT FOR SITE


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EQUIPMENT FOR SITEINVESTIGATION

Samples equipment

In place testing (field)

1. Standard penetration test

2. Vane shear test

3. Cone penetration test

4. Pressuremeter test predictingsettlement and shear strength

properties of the soil

5. Piezometer - groundwater

BORING BOREHOLE


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BORING BOREHOLEMETHODS

1. Hand auger the sample taken from the soil

is brought up by the auger (the sample is

disturbed)

2. Rotary drilling

3. Hammer drilling

4. Wash boring

5. Core drilling


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FIELD TEST

1. Standard Penetration Test (SPT)

2. Cone Penetration Tets (CPT)

3. Plate Load Test

4. Trial Test

Observation of ground water

1. Vertical pipe2. Piezometer


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FIELD TEST

Standard Penetration Test (SPT)

This test is the most common strength test

conducted in field. It is used with all soil except

gravel and it often used directly for the design of

foundation.


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FIELD TEST

Cone Penetration Tets (CPT)

the cone itself is to forced an additional distance

by inner rods, without the drill rods moving

through the soil.

CRITERIA IN DETERMINING


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CRITERIA IN DETERMININGTHE NUMBER OF SAMPLING

The number and depth of test holes depend

on the structure to be built, the type of soil,

and the variation in the soil profile found.

1. One story buildings

Test holes are drilled 30-60m apart (distant) to a

depth of 6-10m, with one deeper hole to check

the deeper soils.



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2. Four story buildings

Test holes are drilled 15m-30m apart (distant) to

a depth of 10-15m, with some holes to a depth

one and one-half times the width of the building

and at least one deep hole to bedrock

3. Highways

Test holes are drilled approximately 300m apart

to depth of 3m below subgrade level



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Samples and field tests (for the first few holes)

are taken in every soil layer or every 1.5m

(5ft), whichever is less.


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TYPE OF SAMPLING

1. Thin walled sampler/shelby tube

2. Open drive sampler

3. Separate drum sampler/split spoon sampler

4. Stationary piston sampler

5. Continuous sampler

6. Compressed air sampler


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TYPE OF SAMPLINGThin walled sampler/shelby tube

The sampler is attached to drill rods, lowered to

the bottom of the hole, and pushed into the soil

in one smooth motion; the sample is waxed

when removed; the sample is undisturbed. Thistechnique is used only in clays and silts

Separate drum sampler/split spoon sampler

The spoon is lowered to the bottom of the hole,attached the drill rods, and driven into the soil;

the sample is disturbed. This technique is use d

in all soils

SITE INVESTIGATION


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SITE INVESTIGATIONREPORT

1. Content of Site Investigation Report

2. Borehole logs

SITE INVESTIGATION


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SITE INVESTIGATIONREPORT

Content of Site Investigation Report

Summary of the test program

General description of the soil condition

Detailed analysis of each type of soil

Recommendations for design (as required)

Test hole logs and the soil profile


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SITE INVESTIGATION REPORT

Borehole logs include:

1. Sample number, depth and type

2. Field test, depth and result

3. Depth to layer changes

4. Field soil description

a) Type of soil grains

b) Moisture conditions

c) Consistency or density

d) Seams (layers) and stratification

e) Other distinguishing features

Example map showing boring


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Example map showing boringlocation on 150-ft by 300-ft


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BORING LOG SHEET

NUMBER AND DISPOSITION OF


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NUMBER AND DISPOSITION OF

TEST LOCATION

For compact building site covering an area of

about 0.4 hectare, one bore hole in each

corner and one in the centre should be

adequate For smaller and less important building, even

one hole in the centre will suffice

For very large areas covering industrial andresidential colonies, the geological nature of

the terrain will help in deciding the number of

bore holes.


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In general, dynamic or static cone may be

performed at every 100m by dividing the area

in grid pattern and the number of bore holes

may be decided by examining the variation inthe penetration curves.

V.N.Vazirani : Handbook of civil Engineering ,

Khanna Publishers (2008)

DEEP OF BORINGS FOR


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DEEP OF BORINGS FORFOUNDATION

Explore soil to the depth to which it will be

significantly stressed.

This is often taken as the depth at which the

vertical total stress increase due to thefoundation is equal to 10% of the stress

applied at foundation level


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Borehole depths for foundations


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ASSIGNMENT 1 (GROUP)


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Explain boring borehole method Hand Auger

Rotary drilling

Hammer drilling Wash boring

Core drilling



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Explain types of sampler

Thin walled sampler

Open drive sampler Separate drum sampler/split spoon sampler

Stationary piston sampler

Continuous sampler

Compressed air sampler


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Explain field test carried out on site. Explanations

include the standard of the test, method on the site

and diagram/picture that equipment.

Standard Penetration Test (SPT) Cone penetration test (CPT)

Plate load test

Trial test

Vertical pipe

Piezometer

Documents

Topic 1 Site Investigation PDF