BS 368-1971 Precast Concrete Flags

B S I B S * 3 b B 7 1 ~ ~ ~ L b 2 4 h b î 0006042 4

BRITISH STANDARD 368 : 1971 UDC 625.882:625.815 :666.972-41

SPECIFICATION FOR

PRECAST CONCRETE FLAGS

BRITISH STANDARDS INSTITUTION

I I COPYRIGHT 2003; British Standards Institution on ERC Specs and Standards

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BSI BS*3bB 71 W l b 2 4 b b î 0 0 0 6 0 4 3 b W

SPECIFICATION FOR

PRECAST CONCRETE FLAGS

BS 368 : 1971 Incorporating amendments issued June 1976 (AMD 2030) and

December 1979 (AMD 3054)

BRITISH STANDARDS INSTITUTION Incorporated by Royal Charter

2 PARK STREET, LONDON W1A 2BS Telex: 266933 Telephone: 01-629 9ûûû

I

COPYRIGHT 2003; British Standards Institution on ERC Specs and Standards


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BSI BS*3bB 71 I 1b24bb7 000604q B

BS 368 : 1971

THIS BRITISH STANDARD,. having been approved by the Cement, Lime and Gypsum Industry Standards Committee was published under the authority of the Executive Board on 25 March 197 1. 0 British Standards Institution, 1971. First published, August, 1929. First revision, May, 1936. Second revision, January, 1956. Third revision, March, 1971. SBN: 580 06209 O The Institution desires to call attention to the fact that this British Standard does not purport to include all the necessary provisions of a contract. This standard makes reference to the following British Standards: BS 12. Portland cement (ordinary and rapid hardening). BS 146. Portland-blastfurnace cement. BS 340. Pre-cast concrete kerbs, channels, edgings and

quadrants. BS 812. Methods for the sampling and testing of mineral

aggregates, sands and mers. BS 882. Coarse and h e aggregates from natural sources. BS 915. High alumina cement. BS 1014. Pigments for cemenf, magnesium oxychloxide and

BS 1047. Air-cooled blastfurnace slag coarse aggregate for

BS 1201. Aggregates fDr granolithic concrete floor finishes. BS 1610. Methods for the load verification of testing

machines. BS 2648. Performance requirements for electrically-heated

laboratory drying ovens. BS 3892. Pulverized-fuel ash for use in concrete. BS 4027. Sulphate-resisting Portland cement. BS 4484. Measuring insfruments for constructional works.

Part 1. Metric graduation and figuring of instruments for linear measurements.

concrete.

concrete.

The following BSI references relate to the work on this standard: Committee reference CEE/6/4 Draft for comment 70/2631

8709'-4- 0.4k- B

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i BSI BSr3bB 71 lb24bb7 0006045 T i

CONTENTS

Co-operating organizations Foreword

1. Scope 2. Cement 3. Aggregates

SPECZFICATION

3.1 Quality 3.2 Maximum size

4. Other materiais 4.1 Pulverized-fuel ash 4.2 Pigments 4.3 Others

5. Finish and colour 6. Casting and curing

6.1 Casting 6.2 Curing 6.3 Work in cold weather

7. Dimensions and tolerances 7.1 Dimensions 3.2 Tolerances

8. Test requirements

90 1 o. 1 1 .

12. 13.

8.1 Transverse strength 8.2 Absorption of water Manufacturer's certificate Facilities for sampling Samples for testing 1 1 . I General 11.2 Purchaser's sampling 11.3 Sampling for independent testing Test results Independent tests 13.1 Sampling and testing 13.2 Costs of tests

3

BS 368 : 1971

Page 5 6

7 7 7 7 8 8 8 8 8 8 8 8 8 9 9 9 9

10 10 I I 11 11 11 11 12 12 12 12 12 12

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BSI BS*3bd 71 1b29bb î OOObOqb 1 m

BS 368 : 1971

APPENDICES Page 13 13 14

A. Methods of measuring B, Test for transverse strength C. Test for absorption of water

TABLES

9 10 11

1. Flag dimensions 2, Transverse strength requirements 3. Water absorption limits

FIGURES 15 1. Notched straightedge and gauge block

2. Arrangement of loading for transverse strength

3. Arrangement of loading for transverse strength 16 tat; side elevation

test; end elevations 16

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BSI BS*3b¿i 71 U Zb24bb ï 0006047 3 I

BS 368 : 1971

CO-OPERATING ORGANIZATIONS

The Cement, Lime and Gypsum Industry Standards Commit- tee, under whose supervision this British Standard was prepared, consists of representatives of the following Government departments and scientific and industrial organizations: Association of Consulting Engineers

*British Precast Concrete Federation 'British Quarrying and Slag Federation British Railways Board British Ready Mixed Concrete Association British Steel Industry

*Cement and Concrete Association *Cement Makers' Federation Chalk Quarrying Association Chemical Industries Association Concrete Society Limited Federation of Civil Engineering Contractors Greater London Council Gypsum Products Development Association

*Institution of Civil Engineers *Institution of Municipal Engineers *institution of Structural Engineers Institution of Water Engineers Ministry of Housing and Local Government Ministry of Public Building and Works

*Ministry of Public Building and Works Building Research

*Ministry of Transport

*Sand and Gravel Association of Great Britain

Station

National Federation of Building Trades Employers Royal Institution of Chartered Surveyors

Society of Chemical Industry Welwyn Hall Research Association

The Government departments and scientific and industrial organizations marked with an asterisk in the above lisf, together with the following, were directly represented on the Committees entrusted with the preparation of this Standard: County Surveyors' Society Institute of Landscape Architects Ministry of Transport-Road Research Laboratory Modular Society National Paving and Kerb Association Road Improvement Association Royal Institute of British Architeits

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. BSI BS*3bB 71 W l b 2 4 b b 9 000b048 5

BS 368 : 1971 BRITISH STANDARD SPECIFICATION FOR

. PRECAST CONCRETE FLAGS FOREWORD

This British Standard, which was &st issued in 1-929, was revised in 1936 and 1956, and has been revised again in the light of present-day practice in the manufacture of concrete flags under the authority of the Cement, Lime and Gypsum Industry Standards Committee. Considerable changes have been made to this standard both to ifs technical requirements and to the arrangement of the clauses.

The clauses dealing with maferiais have been revised to take into account revised and new British Standards, and this standard specifies the requirements for the use of pulverized-fuel ash in concrete flags.

The dimensions and tolerances permitted are given in metric units and the methods of measuring the flags are given in a new appendix.

Since flags are normally tested in a testing machine rather than by applying loads to a simply supported specimen, the relevant appendix has been revised to describe both the requirements of the testing machine and the testing procedure. As a result of further research conversion factors are given for the required transverse strength at ages beyond 28 days. These factors are identical with those given in BS 340*.

As a result of research work on durability and the method of performing the test for absorption of water, the previous tests at 10 min and 24 h have been deleted and replaced by a 30 min absorption test. This test is carried out on specimens sawn from the comers of the flag, to give more uniform results, instead of cut as previously. Due to the change in the test procedure the absorption iimit has been changed and different values are given for different ages at test and a requirement for the flakiness index of the coarse aggregate has been added.

I t has been found that Hags manufactured by some processes, which would have complied with the 24 h absorption test of the previous edition of the standard, generally could not meet the water absorption Ifmits of the new 30 min test because of their different construction characteristics. As there now appears to be suftkient evidence to prove that these flags are durable, the responsible Technical Committee have raised the absorption limits given in Table 3 by approximately IO % for all flags.

The rate of wear test has been deleted but an additional requirement for the mechanical strength of the aggregate is given.

The clauses dealing with methods of manufacture and with the colour, h i s h and freedom from defects have been revised and re-arranged.

BS 340, ‘ Pre-cast concrete kerbs, channels, edgings and quadrants ’. 6



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BSI BS*3bB 71 II Lb24bbî 000b049 7

’With the increasing number and size of vehicles, experience has shown that, when footpaths are subjected to these traffic loadings, the existing range of paving flags, A to D, can occasionally suffer damage. A range of paving flags E, F and G, of smaller plan area has been introduced, which with a suitable foundation is specifically designed to withstand these loadings.

The development of flags of smaller plan area has resulfed in greatly improved performance of footways suffering occasional heavy-vehicle overrun. Field trials have confirmed laboratory findings and shown that the amount of cracking and the development of ‘trips’ is much less with smaller flags, which in turn leads to safer footways and lower maintenance.’

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E S 1 BS*3bA 71 W 1b2Llbbï 000b050 3 W

BS 368 : 1971

In accordance with the change to the metric system, this standard has been prepared giving values in terms of SI units. For further information on SI units, reference should be made to BS 3763, ' International System (SI) units,' and PD 5686, ' The use of SI units.' NOTE. Attention is drawn to certification facilities offered by BSI; see the back cover of this standard.

SPECIFICATION 1. SCOPE

This British Standard specifies requirements for precast paving flags manufactured from a concrete mixture in a range of sizes and thicknesses for use in the construction of footways and other paved areas.

2. CEMENT

The whole of the cement used in the manufacture of the paving flags shall comply with one of the following British Standards:

or BS 12, ' Portland cemenf (ordinary and rapid hardening) ',

BS 146, ' Portland-biastfurnace cement '. When specially ordered by the purchaser, high alumina cement complying

with BS 915*, or sulphate-resisting Portland cement complying with BS 40271., or hydrophobic cement complying with the physical requirements of BS 121, or white or coloured Portland cement complying with BS 12, may be used.

3.1 Quality. The fine and coarse aggregate shall consist of either naturally occurring materials, crushed or uncrushed, complying with BS 882 : 1983 --?-

{except grading requirements in Clause .S)$ ,'. or alternatively coarse aggregate complying with.'Clause 4 of BS 1047 : 1983. (except grading requirements in 2 4.8)fi'. may be used. -.

ifie coarse aggregate to be used, when tested in accordance with BS 81 2**,

(1) 10 "/: fines test: Not less than 10 tonnes. (2) Flakiness index: Not more than 35 % unless otherwise agreed between

the purchaser and the manufacturer on the basis of acceptable evidence of durability.

BS 915, ' High alumina cemenf '. + BS 4027, ' Sulphate-resisfing Portland cement '. :BS 12, ' Portland cement (ordinary and rapid hardening) '. Q BS 882, 'Specificatiön for aggregates from naturai scurcp-s Kar concrete

''0 BS 1047, 'Specification for air-cooled blastfurnace slag aggregate for use in construction'

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3. AGGREGATES

A shall meet the following requirements:

_ _ - < - .

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BSI BS*368 71 W Lh246h7 000605L 5 m

ES 368 : 1971

3.2 Maximurn'size. The nominal .maximum size of the aggregate shall not exceed 14 mm as specified in BS 882*.

4. OTHER MATERIALS

4.1 Pulverized-fuel ash. 'Where pulverized-fuel ash is used, it shall comply with BS 3892 : Part Or 'i BS 3892 : Part 2t.'

The total sulphate content of the concrete mix shall not exceed 4.0 % as SOa by weight of the cement. The sulphate content shall be calculated from the known sulphate contents of the cement, aggregates (where applicable) and pulverized-fuel ash, as determined by tests carried out in accordance with the requirements of BS 12$, BS 10479 and BS 38921. respectively.

4.2 Pigments. Any pigments used in the colouring of the flags shall comply with BS 101411.

4.3 Others. Any additional material required to produce special properties such as a special texture, colour or grip shall not have any deleterious effect upon the concrete.

5. FiNISH AND COLOUR Special surface fìnishes may be agreed upon between the vendor and the purchaser. Au. arrises shall be clean and sharp.

Unless otherwise specified by the purchaser, the flags shall be supplied in natural colour. When the products are ordered coloured, the colour shall be agreed between the vendor and the purchaser at the time of placing the order. The vendor and purchaser shali agree whether the products shall be coloured throughout or only in a surface layer. In the latter case the surface layer shall be not less than 12 mm thick and cast as an integral part of the flag. - .

6. CASTING AND CURING

6.1 Casting. The flag may be made by any process. The escape of the finer particles of mortar during the process of manuîacfure shall be prevented as far as practicable.

A flag described as ' pressed ' shall only be made by employing a pressure of not less than 7 MN/ma over the entire surface receiving the pressure.

6.2 Curing. After casting, the flap shall be stored so as to prevent undue loss of moisture particularly during the early stages of curing.

* BS 882, ' Coarse and fme aggregates from natural sources '. y BS 3892, 'Pulverized-fuel ash', Part 1, 'Specification for pulverized-fuel ash for use as a cementitious component in structural concrete' and Part 2, 'Specification for pulverized-

. fuel ash for use in grouts and for miscellaneous uses in concrete'.' T BS 12, ' Portiamwment (ordmary and rapid hardening) '. 8 BS 1047, ' Air-cooled blastfurnace slag coarse aggregate for concrete '. N BS 1014. ' Pigments for cement, magnesium-oxychloride and concrete '.



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BSI BS*3bA 71 m L b 2 q b b ï 000b052 7 m

7.2.1 Thickttess. The average thickness of the twelve values obtained from the four measurements on each of the three flags shall be within f 3 mm of the specified thickness.

7.2.2 Lergth and width. Each individual flag of the sample shall be within the maximum and minimum limits of manufacturing size specified in 7.1.

I A I

‘7.3 Chamfer. A wearing surface edge chamfer with dimensions, measured at right angles to one another, not exceeding 5 mm vertically and not exceeding 7 mrn horizontally shall be permitted. NOTE. Flag types E, I: and C will be provided with chamfers unless otherwise specified by fhc purchaser. Flag types A, B , C and D will not be provided with chamfers unless otherwise specified by the purchaser.

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BS 368 : 1971

6.3 Work in cold weather. Special precautions shall be taken to prevent the temperature of the concrete falling to 0°C during the early stages of hardening, ViZ :

(1) The temperatureof the concrete at the time of placing shall be at least 5 O C . (2) The temperature of the mould itself shall be above 0°C. (3) No material which has been exposed to temperatures below 0°C shall

Flags shall be protected from damage by frost.

be used until it has been completely thawed.

7. DIMENSIONS AND TOLERANCES

7.1 Sizes. Flags shall have the sizes for the appropriate type given in Table 1.

- Flag type

-

A

B

C

D

E

F

G -

Table 1. FLAG SIZES I

Plan sizes ~ ~~

Co-ordinating size

mm

600 X 450

600 X 600

600 X 750

600 X 900

450 X 450

400 X 400

300 X 300

Work size

mm

598 X 448

598 X 598

598 X 748

598 X 898

448 X 448

398 X 398

298 X 298

Maximum limit of manufacturing size

rnm

600 X 450

600 X 600

600 X 750

600 X 900

450 X 450

400 X 400

300 X 300

Minimum limit of manufacturing size

mm

596 X 446

596 X 596

596 X 746

596 X 896

446 X 446

396 X 396

296 X 296

Work size thickness

mm

A 50 or 63

50 or 63

50 or 63

50 or 63

l 50or70

50 or 65

50 or 60

NOTE. When flags are being ordered, it will be necessary only to specify the type ._ followed by the thickness, e.g. 'F 50'. - - - - . -. -

7.2 Tolerances. When sampled in aecordiince with Clame 1 i and masuted as described in Appendix A. the flags sampled shall be within the tolerances given in 7.2.1 t o 7.2.4.

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BSI BS*3bB 71 9 1b24bb ï 000605Li O =

I:lay type

A

B , C o r D

e

1:

c

BS 368 : 1971

Mininiuni ïaailiiiy load

50mm 60mm 63 mm 65 nim 70mni thick thick thick thick thick

kN kN kN kN kN

8.3 12.7

11.1 16.9

9.6 18.8

9.1 15.4

9.6 13.8

7.2.3 Sguareness of platt. The difference between the two diagonals measured on the same face of each individual flag of the sample shall not exceed 3 m m

7.2.4 Flatness, winding und bowing. The maximum deviation from the specified straightedge placed in any position on the wearing surface of each individual flag ofthe sample shall not exceed 2 mm.

The flatness etc. shall be measured by means of the appropriate notched straightedge. and the 25 mm x 25 mmx 4 mm test gauge shown in Fig. 1.

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8. TEST R E Q U I R E m S

The Bags sampled in accordance with the provisions of Clause 11 shall comply with the following test requirements for transverse strength and absorption of

. . ... water.

8.1 Transverse strength. The failing loads of individual flags when tested in the manner described in Appendix B shall be not less than the appropriate value given in Table 2.

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6 BSI B S U 3 6 8 71 m 1 6 2 4 b b ï 0006055 2 m

Age of sample at test Months

2 3 4 5 6 and over

Conversion factor

1.10 1.15 1 -20 1 -25 1-30

Convirsion factors for Intermediate ages shall be obtained by linear interpolation.



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BS 368 : 1971

8.2 Absorption of water. When tested in the manner described in Appendix C the average increase in weight of the test pieces from each flag shall not exceed the value appropriate to the age of test given in Table 3.

Age of sample at test

Maximum average absorption by weight

u p to 1 2 3 4 5 6 and over

4.0 3.5 3.3 3.2 3. I 3.0

I

Maximum average absorption values for intermediate ages shall be obtained by linear interpolation. -

Y. MANUFACTURER’S CERTIFICATE

The manufacturer shall satisfy himself by regular testing that at the time of delivery the flags comply with the requirements of this British Standard and, if requested, shall forward a certificate to this effect to the purchaser or his representative.

The manufacturer shall, if requested to do so, supply a certificate stating the date of manufacture of the flags.

10. FACILITIES FOR SAMPLING

The purchaser or his representative shall at ail reasonable times have access to the place where the flag, are manufactured or stored, for the purpose of examining and sampling the materials and the finished flags, inspecting the process of manufacture, and marking the flags. The vendor shall, free of extra charge, provide or make arrangements for the provision of such facilities and labour required for examination, sampling, inspecting and marking before delivery as may be necessary to establish that the flags comply with the requirements of this standard.

11. SAMPLES FOR TESTING

11.1 General. When required the samples shall be taken at random from the appropriate consignment representing the whole or part of the order; these samples may be taken as required in 11.2 or 11.3.



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' BSI BS*3bA 7 2 m Zb24bbî 000b057 b =

BS 368 : 1971

11.2 Purchaser's sampling. For the checking of the dimensions specified in Clause 7 and for carrying out the tests specified in Clause 8, the purchaser or his representative may take before or immediately after delivery three sample flags for every order for 2000 or less. For orders for more than 2000 flags, three sample flags may be taken from every 2000 flags forming pact of the order.

11.3 Sampling for independent testing. When it is agreed that independent testing as described in Clause 13 is required, the random sample of three flags shall be selected and marked when both the purchaser and the manufacturer, or their representatives, are present.

12. TEST RESULTS

Should any of the test results not comply with the requirements of Clauses 7 or 8, then the whole of the consignment of 2000 flags, or less, comprising the whole or part of the order, shall be deemed not to comply with this standard.

13. INDEPENDENT TESTS

13.1 Sampling and testing. If requested by the manufacturer, or the purchaser, independent tests shall be carried out by a mutually-agreed, independent testing laboratory whose results shall be accepted.

The samples required for these independent tests shall be taken as specified in Clause 1 I, measured and tested in accordance with Clauses 7 and 8 and the test results judged as specified in Clause 12.

13.2 Costs of tests. Unless otherwise specified at the time of the enquiry and order, the cost of the independent tests shall be borne as follows:

(i) By the manufacturer, in the event of results showing that the flags do not comply with the standard.

(2) By the purchaser, in the event of the results showing that the flags comply with the standard.

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. i COPYRIGHT 2003; British Standards Institution on ERC Specs and Standards


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BS 368 : 1971

APPENDIX A

METHODS OF MEASURMG A.l Thickness. The thickness of each of the three sample flags is measured with a caliper gauge having jaws suitable for measuring the thickness 30 mm in from the edge of the flag. The thickness of each flag is measured 30 mm in from the edge of the flag at a distance not more than 100 rnm from each comer. The four measurements obtained from each of the three flags give twelve results, the average of these is calculated and expressed to the nearest 1 mm. A.2 Length and width. The length and width of each of the sample ñags is measured at any position across the wearing fa+ with a steel tapecomplyingwith the requirements of BS 4484* and are expressed to the nearest 1 mm. A.3 Squareness of plan. The squareness of plan of each of the sample flags is determined by measuring the two diagonals of the wearing face with a steel tape complying with the requirements of BS 4484* and these dimensions are expressed to the nearest 1 mm. A.4 Flatness, winding and bowing. Flatness, winding and bowing are measured by means of the appropriate notched straightedge and gauge block, both made of steel, shown in Fig. 1. When the notched straightedge is placed in any position on the wearing face of each sample flag, if the surface of the flag touches the notched section of the straightedge, both the support ends of the notched straightedge shall be in contact with the flag. Also, when placed in any position on the wearing face ofeach flag, the gauge block shall not pass between the notched straightedge and the surface ofthe flag.

As amendid . Der. 1979

APPE"X B

TEST FOR TRANSVERSE STRENGTH B.1 Testing machine. The transverse testing machine complies with the requirements of a Grade A or Grade B m a c h e when verified in aceordance with BS 1610t and is of sufficient capacity to apply loads 50 %higher than is required in Clause 8 @.e. 25 kN). It is provided with two steel supporting rollen each 38 mm diameter, spaced 450 mm between centres. for types A, B, C and D; 375 inm for type E: 350 niin for type F; ?SO min for type G.Alternatively two steel bearers each 6 mm wide on the supporting surfaces, spaced 450 nìm ,350 mn1 Or 250 mm apart internally, may be used. In either case, one support is horizontal and the other is so mounted, e,g. by pivoting about an axis parallel to the length of the specimens,

BS 4484, ' Measuring instruments for constructional works ', Part 1, ' Metricrgraduation land figuring of instruments for linear measurements '. 't BS 1610, ' Methods for the load verification of testing machines '. x I f convenient, 457 mm spacing may bz used.

375 inm ,

it', , . \ :I 3.\, I.

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BSI BSm36A 71 m 3b2Libhî 0006059 T m

BS 368 : 1971

as to enable loads to be applied without inducing my torsional restraint in the specimen. The upper member of the loading frame is provided with a spherical seating to ensure that the load is applied axially and without inducing any torsion in the specimen, and a steel platen at least 50 mm wide and of length not less than the width of the widest specimen to be tested, normally 600 mm (se Figs 2 and 3).

B.2 Testing procedure. Place the specimen symmetrically on the bearers of the testing machine and with its shorter sides parallel to the supporting rollers or bearers.

The load is applied through the medium of a hardwood fillet 50 mm wide, on the upper surface of the specimen at the midpoint of the span and extending the whole width of the specimen parallel to the supporting rollers or bearers.

Apply the load steadily and uniformly starting from zero, at a rate not exceed- hgO.75 kN per 10 s for flag types A, E, F and G and 1.0 kN per 10 sfor flag types B, C and D.(measured parallel to the bearers), until the specimen breaks Orthe capacity: A Of the machine k reached. Record the individual failing loa& in the &port, 1 except that when a specimen does not fail at the upper limit of testhg machine,. record the f a h e , - load - - - as ‘-greater than -kN ’.

!

APPENDIX C

TEST FOR THE ABSORPTION OF WATER

C.1 Apparatus. The following apparatus is required: (i) Suitable concrete sawing machine. (2) Balance capable of weighing up to 2 kg to an accuracy of 1 g. (3) Well ventilated oven complying with BS 2648* in which the temperaiure

(4) Desiccator or small, dry, airtight vessel to contain the specimens. (5 ) Tank approximately 150 mm deep in which the specimens can be

. is controlled to between 100°C and 105°C.

immersed in’water.

C.2 Preparation of test pieces. Two square test pieces are sawn from diagonally. opposite comers of each of the three sample flags. These test pieces are approximately 100 mm x 100 mm, sawn from the full thickness of the flag and have two sawn and two moulded edges.

BS 2648, ’ Performance requirements for electrically-heated laboratory drying ovens ’.

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BS 368 : 1971

'C.3 Testing procedure. Place the six test pieces in the drying oven at the same t h e so that they are not nearer than 25 mm to any heating surface or to any other test piece, and dry them in the oven for 72 f 1 h. On removal from the oven, cool them for 24 f 1/2 h in the desiccator or in the small, dry, airtight vessel. Then weigh each test piece and immediately immerse it in water, the temperature of which shall be 20 f 2"C, for a period of 30 min i- 30 s. Immerse the test pieces flat, supported on glass rods or a plastics mesh, at a depth such that there is 25 f 5 mm of water over the top of each test piece. At the end of the 30 min immersion, remove the test pieces, shake them to remove the bulk of the water and then dry them with a cloth as rapidly as possible until all the free water is removed from the surfaces. Immediately weigh each test piece again.

Calculab the percentageabsorption of each test piece by dividing the increase in weight of the test piece by its dry weight, and report the result to the nearest 0.1 %.

Len gt h 550 for type Aand 6 flags 700 for type C flags 850 for type D flags 400 for type E flaas 350 for type F f ~

250 for t y p e G flaas,

50 t ? - Gauge block +-YA

M 5 ' 5

AU dimensions in miiiimetres Fig. I . Notched straightedge and gauge block

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BS 368 : 1971

Locatin bars removed Hardwood before &ding is

a:. 2. A , , fil let -9 [commenced i , Fig. 2. Arrangement of loading for transverse strength test; side elevation.

Flag

Section B-B

&

1 I Flag

I

Section C-C

Fig. 3. Arrangement of loading for transverse strength test; end elevations

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B S I BS*3bB 71 m Lb24669 000b062 T m

Anieiidiiliciit No. 3 yirblislicd aiid effective fro in 29 August 1986

to US 368 : 1971

Precast coiicrete flags

NOTE. This aiiicxirneiit lias bccii publislied peiidiiig tlic piiblicatioii of a new ßritisli Staiidard for concrete kerbs niid lkigs, wliicli i s iiiteiidcd io siipcrscdc 11s 368 aiid US 340

Revised text

Foreword (as ainerided by Aineridinent No. 1). Delete the last paragrapli and substitute the following. ‘Witli tlie increasing riiiiiiber arid size of veliicles, experience lias sliowii tliat, when footpatlis are subjected to tliese traffic loadings, the existing range of paving flags, A to D, can occasionally suffer damage. A range of paving flags E, F and G, of snialler plaii area lias been introduced, wliicli with a suitable foiiiidation is specifically designed to witlistand tliese loadings.

The developniciit of flags of siiialler plan area lias resulted in greatly improved performance of footways suffering occasional heavy-veliicle overruii. Field trials liave coiifirnied laboratory findings and shown that tlie atiioiiiit of cr:icking aiid tlie deuelopaieiit of ‘trips’ isiiiucli less with siiialler flags, wliicli in turn leads to safer footways and lower inaiiiteiiaiice.’ Clause 3.1 Quality. In paragraph 1 , lines 2 and 3, delete ‘tlie quality rcquire- iiicnts Of 4a and 5d of BS 882 : 19655, or of 4a aiid 5d of BS 1201 : 196511’, and substitute ‘BS 882 : 1983 (except grading requirements i n Clause 5)$,’. in paragrapii i , lines 4 and 5, delete ‘the quality requirements of Clause 5 of BS i047 : 19521’ and substitute ‘Clause 4 of BS 1047 : 1983 (except grading requirenicnts in 4.8)g’. Delete the footnote to BS 882 and substitute tlie following. ‘3 BS 882, ‘Specificdtion for aggregdtes from natural sources for concrete’.’

Delete tlie footnote to BS 1201. Dzletc tlie footnote to BS 1047 and substitute tlie following ‘9 BS 1047, ‘Specification for air-cooled blastfiiriiace shg aggregate for use iii construction’.’

Clause 4.1 Pulverized-fuel asli. Delete paragraph i and substitute the following. ‘Wliere pulverized-fuel asli is used, it shall comply with BS 3892 : l’art It or BS 3892 : Part 2i.’ Delete the footnote to BS 3892 and substitute tlic following.

’f. BS 3892, ‘Pulverized-fuel di’, Fart 1, ‘Specification for pulverized-fuel u l i for use us a ceiiicntitious coiiiponcnt in structural concrete’ and Part 2, ‘Speciíication for pulverized- fuel asli for use in grouts aiid for miscellaneous uses in concrete’.’

‘



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Work size

- Flag type

-

A

n

C

D

E

1;

G

inin

598 x 448

598 x 598

598 x 7413

598 x 898

448 x 448

398 x 398

298 x 298

- I'lnii sizes

Co-ordiiiatiilg SiLC

111111

600 X 450

600X GOO

600 X 750

600 X 900

450 X 450

400 X 400

300 X 300

liniit of liniit of

size size

niiii

600 X 450

600 X 600

600 X 750

600 >: 900

450 X 450

400 X 400

300 X 300

nini

596 X 446

596 X 596

596 X 746

596 x a96

446 X 446

396 X 396

296 X 296

Work size tliickncss

nim

50 or 63

50 or 63

50 or 63

50 or 63

50 or 70

50 or 65

50 or 60

2 [AMD 51741



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, . I , Table 2 Transverse strciigtli requireiticnts. Delctc the table iiew Table 2 .

T d l c 2. TRANSVERSE STRBNGTII REQUIREMENTS !

Flag typc

---

A

U,C‘orD

B

F

G --

[id substitut

hiiiiiiriuiii failing load

50 niiii thick

kN

8.3

11.1

9.6

9.1

9.6

60 nini thick

kN

13.8

63 nini thick

kN

12.7

16.9

65 niiii thick

kN

15.4 II.

70 i n i n thick

kN

18.8

eh

Clause B.1 Testiiig iiiaciiiiie. In line 5, after ‘between centres’ itisert ‘for types A, B , C and D; 375 111111 for type E; 350 inni for type F; 250 mm for type G.’ In line 6, after ‘450 mm *’ insert ‘, 375 min, 350 mm or 250 min’.

. _

I

3 [AMD 51741



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_.- I :

C h s c 11.2 ‘Yestirig proccdirre. Iii paragraph 3, liiie 2, delete ‘0.75 kN pcr 10 s L’or slabs 450 111111 wide and 1 .O kN pe; 10 s for slabs 600 inn wide’ arid substiliite ‘0.75 kN per I O s for flag typcs A, E, Ii aiid G and 1.0 kN pcr 10 s for íl:ig types U, C and il’. Pig. 1. Nofclicd straightedge aiid gaiige block. (as mended by Anieiidiiicrit No, 2). Deletc figurc 1 aiid substitute tlic ncw figure 1.

Len 3i h 550 for type A and 8 flogs 700 fcr type C flags 050 for type D flags 400 for type E flags 350 for type F flags 250 for type G fiaqs,

’O1 u/ n k 2 5 5

NI dinieiisions in niillimetres Fig. 1. Notched straightedge and gauge block

Gauge block

4 [AMD 51741



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B S I B S * 3 6 8 71 m 3624669 00060bb 7 =

Fig. 2, Arrsiigeiiieiit of loadiiig for traiisverse strenglii fest; ciid elevation. Dclcte figuic 2 uiid substitutc tlic IICW figure 2.

Locating brs removed y -before load‘ng is

Hardwood 111 let commenced

I

l I

I l I I

I f

+, 450,375,350 or-250 mm (see B.l)

C -

Fig. 2. Arrangement of loading for transverse strength test; side elcvation.

I

8608-2-1.6k-B 5 RDB/32 [AMD 51741



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Documents

BS 368-1971 Precast Concrete Flags