ICS 93.080.10  
 
Reference number  
DRS  265: 2021  
© RSB 2021  
  
 RWANDA 
STANDARD  DRS  
265  
 
Second  edition  
2021-mm-dd 
 
Precast reinforced concrete pipe culvert — 
Specification  
 
   
DRS 265: 2021  
©RSB 2021  - All rights reserved                  ii 
 In order to match with technological development and to keep continuous progress in industries, 
standards are subject to periodic review. Users shall ascertain that they are in possession of the latest 
edition  
 
 
 
 
 
 
 
 
© RSB 2021  
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized 
in any form or by any means, electronic or mechanical, including photocopying and microfilm, without 
prior written permission from R SB. 
Requests for permission to reproduce this document should be addressed to : 
Rwanda Standards  Board  
P.O Box 7099 Kigali -Rwanda  
KK 15 Rd, 49  
Tel. +250 788303492  
Toll Free: 3250  
E-mail: info@rsb.gov.rw  
Website: www.rsb.gov.rw  
ePortal: www.portal.rsb.gov.rw   DRS  265: 2021  
iii                ©RSB 2021 - All rights reserved  
 Contents  Page 
1 Scope  ................................ ................................ ................................ ................................ .............  1 
2 Normative references  ................................ ................................ ................................ ...................  1 
3 Terms and definitions  ................................ ................................ ................................ ..................  1 
4 Materials  ................................ ................................ ................................ ................................ ........  3 
5 Design  ................................ ................................ ................................ ................................ ............  4 
6 Manufacture  ................................ ................................ ................................ ................................ .. 6 
7 Physical properties  ................................ ................................ ................................ ......................  7 
8 Inspection  ................................ ................................ ................................ ................................ .... 12 
9 Rejection  ................................ ................................ ................................ ................................ ..... 12 
10 Marking  ................................ ................................ ................................ ................................ ........  12 
Annex  A (normative)  Methods of testing the resistance to proof load  ................................ .............  14 
Annex  B (normative)  Method of testing ultimate load  ................................ ................................ ........  17 
Annex  C (normative)  ................................ ................................ ................................ ...............................  18 
 DRS 265: 2021  
©RSB 2021  - All rights reserved                  iv 
 Foreword  
Rwanda Standard s are prepared  by Technical Committees and approved by R wanda Standards Board (RSB) 
Board  of Directors in  accordance with the procedures of RSB, in compliance with Annex 3 of the WTO/TBT 
agreement on the preparation, adoption and application of standards.  
The main task o f technical committees is to prepare national standards.  Final Draft Rwanda S tandards adopted 
by Technical committ ees are ratified  by me mbers of RSB Board of Director s for publication and gazettment as 
Rwanda Standards.  
RS 265 was prepared by Technical Com mittee RSB/TC 009, Building materials and civil engineering . 
In the preparation of this standard, reference was made to the following standard s: 
1) ASTM C76M – 20, Standard Specification for Reinforced Concrete Culvert, Storm Drain, and Sewer Pipe   
2) IS 458:  2021 , Precast concrete pipes (with and without reinforcement) – Specification   
3) SANS 677: 2020 , Concrete non -pressure pipes  
4) ASTM C497 – 20: Standard Test Methods for Concrete Pipe, Manhole Sections, or Tile  
5) ASTM C822 – 20: Standard Terminology Relating to Concrete Pipe and Related Products  
The assistance de rived from the above source is hereby acknowledged with thanks.  
This second edition cancels and replaces the first edition (RS  265: 2015) of which has been technically revised.  
Committee membership  
The fo llowing organizations were represented on the Technical Committee on Building materials and civil 
engineering (RSB/TC 009) in the preparation of this standard.  
B. J Construction Ltd  
Bridge to Prosperity  
City of Kigali  
Green Pact Africa  
MASS Design  
NPD Ltd  
Rwanda Housing Authority (RHA)  DRS  265: 2021  
v                ©RSB 2021 - All rights reserved  
 Rwanda Inspectorate , Competition  and Consumer Protection Authority (RICA)  
University of Rwanda/College of Science and Technology (UR -CST)  
Rwanda  Standards Board  (RSB) – Secretariat  
  DRS 265: 2021  
1                ©RSB 2021 - All rights reserved  
 Precast reinforced concrete pipe culvert — Specification  
1 Scope  
This Draft Rwanda Standard specifies the requirements and test methods for precast reinforced concrete pipe, 
which  is cylindrical in shape and intended to be used for the conveyance of storm water, and for the construction 
of culverts  (SC) and other intended mainly for sewer and irrigation purposes (SI) . 
2 Normative ref erences  
The following referenced documents are indispensable for the application of this document. For dated 
references, only the edition cited applies. For undated references, the latest edition of the referenced document 
(including any amendments) applie s.  
RS EAS 18 -1, Cement ─ Part 1: Composition, specification and conformity criteria for common cements   
 RS 373 , Aggregates for concrete — Specification   
RS ISO 6935 -1, Steel for the reinforcement of concrete — Part 1:  Plain bars  
RS ISO 6935 -2, Steel for the reinforcement of concrete —Part 2: Ribbed bars  
RS ISO 6935 -3, Steel for the reinforcement of concrete ─ Part 3: Welded fabric   
RS ISO 1920 -3, Testing of concrete — Part 3: Marking and curing test specimens  
RS ISO 1920 -4, Testing of concrete — Part 4: St rength of hardened concrete  
3 Terms and definitions  
For the purposes of this standard, the follow ing terms and definitions apply  
3.1 
admixture  
material  other than water, aggregates, cement and fibre reinforcing used as an ingredient of concrete and added 
to the batch immediately before or during its mixture  
3.2  
cage  
assembled unit of steel reinforcement consisting of circumferential and longitudinal b ars or wires   
©RSB 2021  - All rights reserved                  2 
 3.3  
circular reinforcement  
circular -shaped line of reinforcement  
3.4  
circumferential reinforcement  
reinforcement that is approximately perpendicular to the longitudinal axis of the concrete pipe, box, or structure 
                               
3.5  
culvert  
pipeline intended to convey water under a highway, railroad, canal, or similar facility  
3.6  
D-load  
supporting strength of a pipe loaded under three -edge -bearing test expressed in Newton per linear metre per 
millimetre of inside diam eter or horizontal span  
3.7  
elliptical reinforcement  
line of reinforcement in the approximate shape of an ellipse  
3.8  
line of reinforcement  
circumferential reinforcement comprised of one or more layers  
3.9  
longitudinal reinforcement  
reinforcement,  in a concrete pipe, running parallel to the intended flow  
3.10  
reinforcement  
steel in the form of continuous wire, welded  wire fabric, or bars embedded in concrete in such a manner that 
the above referenced concrete and steel act together to resist stresses  DRS 265: 2021  
3                ©RSB 2021 - All rights reserved  
 3.11  
pipe  
tube or elongated hollow concrete structure intended to transmit flow between locations   
3.12  
ultimate  load 
maximum load that the pipe can withstand  
3.13  
proof load  
load that an acceptable culvert withstands without the development of cracks of width such that the feeler gauge 
can enter to a depth of 2 mm or more over a continuous length of at least 300  mm  
3.14  
splice (reinforcement)  
junction of two sections of parallel reinforcement intended to provide continuity and to transfer forces between 
the two sections  
4 Materials  
4.1 General  
4.1.1  Pipes shall be of concrete. Materials for the concrete shall be so selected as to achieve maximum 
density and minimum porosity. Pipes that are intended to be resistant to chemical attack shall have an 
acceptably low content of material insoluble in hydrochloric acid.  
4.1.2  Reinforced concrete shall consist of cement, mineral aggregates , water  and admixtures, if any,  in which 
steel has been embedded in such a manner that the steel and concrete act together.  
4.2 Cement  
Cement used in the manufacture of the pipes shall comply with requirements for cement compositions given in 
RS EAS 18 -1.  
4.3 Aggregate  
4.3.1  Aggregate shall consist of natural sand, crushed or uncrushed gravel, crushed stone or crushed rock, 
or a combination of any of these aggregates.   
4.3.2  Aggregates used for the manufacture of reinforced concrete pipes sha ll conform to   
©RSB 2021  - All rights reserved                  4 
 RS 373 . The maximum size of aggregate should not exceed one third thickness of the pipe or 20 mm, whichever 
is smaller for pipes above 250 mm internal diameter. But for pipes of internal diameter 80 mm to 250 mm the 
maximum size of aggregate  should be 10 mm.  
NOTE  It is preferable to have the size and grading of aggregates conforming to  RS 373 . It is also preferable that 
materials finer than 75 micron sieve is restricted to 3.0 % by mass.  
4.4 Steel reinforcement  
Steel used for reinforcement shall be free from oil, grease, loose scale and loose or heavy rust. The steel shall 
comply with the requirements of RS ISO 6935 -1, RS ISO 6935 -3and RS ISO 6935 -3, as appropriate.    
4.5 Water  
Water used in the mixing of the concre te shall be clean and acceptably free from impurities that could impair 
the strength or durability (or both) of the concrete.  
4.6 Admixtures  
Admixtures in the concrete may be permitted  and shall comply with the requirements of the respective standards  
4.7 Concre te  
4.7.1  Concrete shall have a compressive strength not less than 35 N/mm2 at 28 days.   
4.7.2  Compressive strength tests shall be conducted on cubes or cylinders as specified in RS ISO 1920 -3 
and be tested accordance with the requirements of RS ISO 1920 -4.  
5 Design  
5.1 General  
5.1.1  The reinforcement shall extend throughout the length of the pipe and shall be so designed that it may 
be readily placed and maintained to designed shape and in the proper position within the pipe mould during the 
manufacturing pr ocess(see figure 1).   
5.1.2  The circumferential and longitudinal reinforcement shall be adequate to satisfy the requirements 
specified in  4.1.  
5.1.3  For non -welded cages spiral reinforcement of the same diameter shall be closely spaced at the end of 
the pipe for a length of 150 mm to minimize damage during handling. The spacing of such end spirals shall not 
exceed 50 mm or half the pitch whichever is less.  DRS 265: 2021  
5                ©RSB 2021 - All rights reserved  
   
Figure1 — Triple cage reinforcement  
5.1.4  The pitch shall also be not less than the maximum size of aggregate plus the diameter of the 
reinforcement bar used.  
5.2 Reinforcement  
5.2.1  Circumferential Reinforcement  
5.2.1.1  A line of circumferential  reinforcement for any given total area may be composed of  two layers for 
pipe with wall thicknesses of less than 180 mm  or three layers for pipe with wall thicknesses of 180 mm or  
greater. The layers shall not be separated by more than the  thickness of one longitudinal plus 6 mm. The multiple 
layers  shall be fast ened together to form a single cage. All other  specification requirements such as laps, welds, 
and tolerances  of placement in the wall of the pipe, etc., shall apply to this  method of fabricating a line of 
reinforcement.   
5.2.1.2  Where one line of circular reinforcement is used, it shall be placed from 35 to 50 % of the wall 
thickness from the inner surface of the pipe, except that for wall thicknesses less than 63 mm, the protective 
cover of the concrete over the circumferential r einforcement in the wall of the pipe shall be 19 mm.  
5.2.1.3  In pipe having two lines of circular reinforcement, each line shall be so placed that the protective 
covering of concrete over the circumferential reinforcement in the wall of the pipe shall be 25 mm.  
5.2.1.4  In pipe having elliptical reinforcement with wall thicknesses 63 mm or greater, the reinforcement in 
the wall of the pipe shall be so placed that the protective covering of concrete over the circumferential 
reinforcement shall be 25 mm from  the inner surface of the pipe at the vertical diameter and 25 mm from the 
 
©RSB 2021  - All rights reserved                  6 
 outer surface of the pipe at the horizontal diameter. In pipe having elliptical reinforcement with wall thicknesses 
less than 63 mm, the protective covering of the concrete shall be  19 mm at the vertical and horizontal diameters.  
5.2.1.5  The spacing centre to centre of circumferential reinforcement in a cage shall not exceed 100 mm 
for pipe up to and including pipe having a 100 mm wall thickness nor exceed the wall thickness for lar ger pipe, 
and shall in no case exceed 150 mm.  
5.2.1.6  The continuity of the circumferential reinforcing steel shall not be destroyed during the manufacture 
of the pipe, except that when agreed upon by the owner, lift eyes or holes may be provided in each pipe for the 
purpose of handling.  
5.2.1.7  If splices are not welded, the reinforcement shall be lapped not less than 20 diameters for deformed 
bars and deformed cold -worked wire, and 40 diameters for plain bars and cold -drawn wire. In addition, where 
lapped cages of welded -wire fabric are used without welding, the lap shall contain a longitudinal wire. When 
splices are welded and are not lapped to the minimum requirements above, pull tests of representative 
specimens shall develop at least 50 % of the mini mum specified ultimate strength of the steel, and there shall 
be a minimum lap of 50 mm. For butt -welded splices in bars or wire, permitted only with helically wound cages, 
pull tests of representative specimens shall develop at least 75 % of the minimum s pecified ultimate strength of 
the steel.  
5.2.2  Longitudinal reinforcement  
Each line of circumferential reinforcement shall be assembled into a cage that shall contain sufficient longitudinal 
bars or members, to maintain the reinforcement in shape and in positi on within the form to comply with 
permissible variations in 5.2.1. The exposure of the ends of longitudinal, stirrups, or spacers that have been 
used to position the cages during the placement of the concrete shall not be a cause for rejection.  
6 Manufactur e  
6.1 General  
The method of manufacture shall be such that the forms and dimensions of the finished pipe are accurate within 
the limits specified in this standard. The surfaces and edges of the pipes shall be well defined and true, and 
their ends shall be sq uare with the longitudinal axis.  
6.2 Concrete mixing and placing  
6.2.1  The aggregates shall be sized, graded, proportioned, and mixed with such proportions of cementitious 
materials ,water and admixtures, if any,  to produce a homogeneous concrete mixture of s uch quality that the 
pipe shall conform to the test and design requirements of this specification. All concrete shall have a water 
cementitious materials ratio not exceeding 0.53 by weight. Cementitious materials shall be as specified in 4.2  
and the produc ed concrete shall as specified in 4.7.1                        
6.2.2  Concrete shall be mixed in a mechanical mixer, mixing shall be continued until there is a uniform  
distribution of the materials and the mass is uniform in colour and consistency, but in no  case shall the mixing 
be done for less than 2 min.  
6.2.3  Concrete shall be placed before setting has commenced. It should be ensured that the concrete is not 
dropped freely so as to cause segregation. The concrete shall be consolidated by spinning, vibra ting, spinning 
combined with vibrations, or other appropriate mechanical means.  DRS 265: 2021  
7                ©RSB 2021 - All rights reserved  
 6.3 Curing  
Pipe shall be subjected to any one of the methods of curing described in 6.3.1 to 6.3.2 or to any other method 
or combination of methods approved by the owner that sha ll give satisfactory results. The pipe shall be cured 
for a sufficient length of time so that the specified D -load is obtained so that the concrete develops the specified 
compressive strength at 28 days.  Exposed surfaces shall be protected from low humidi ty until the concrete has 
reached sufficient maturity for lifting and storage.   
6.3.1  Steam curing  
Pipe shall be placed in a curing chamber, free of outside drafts, and cured in a moist atmosphere maintained 
by the injection of live steam for such time and suc h temperature as needed to enable the pipe to meet the 
strength requirements. At  no time shall the ambient temperature exceed 71 °C. The curing chamber shall be so 
constructed as to allow full circulation around the inside and outside of the pipe.  
6.3.2  Water c uring  
6.3.2.1  Concrete pipe may be water -cured by covering with water saturated material or by a system of 
perforated pipes, mechanical sprinklers, porous hose, or by any other approved method that keeps the pipe 
moist during the specified curing period.  
6.3.2.2  The manufacturer may, at his/her option, combine the methods described in 6.3.1 to 6.3.2 provided 
that the required concrete compressive strength is attained.  
6.3.2.3  A sealing membrane may be applied and should be left intact until the required strength 
requirements are met. All surfaces shall be kept moist prior to the application of the compounds and shall be 
damp when the compound is applied.  
7 Physical properties  
7.1 Internal and wall thickness dimensions  
7.1.1  Permissible deviations  
Any variation in the wall thickness of the pipe shall not exceed the appropriate value given in column 3 of table 
1.  
7.1.2  Internal diameter  
7.1.2.1  The actual internal diameter of a pipe shall not differ from the stated internal diameter by more than 
the appr opriate tolerance given in column 2 of table 1.   
7.1.2.2  Pipe sections that are intended to be jointed to each other shall be furnished with the same internal 
diameter alternative.    
©RSB 2021  - All rights reserved                  8 
 7.1.3  Wall thickness   
The wall thickness shall not vary more than shown in the design or specified wall by more than the appropriate 
tolerance given in column 3 of table 1. Wall thickness more than required in the design is not cause for rejection. 
Pipe having localized variations in wall thickness exceeding those specified above sha ll be accepted if the three -
edge -bearing strength and minimum steel cover requirements are met . 
7.1.4  Length of two opposite sides   
Variations in the laying length of two opposite sides of the pipe shall not be more than 6 mm for all sizes through 
600 mm intern al diameter, and not more than 10 mm/m of internal diameter for all sizes larger with a maximum 
of 16 mm in any length of pipe through 2 100 mm internal diameter, and a maximum of 19 mm for 2250 mm 
internal diameter or larger.  
7.1.5  Length of pipe  
The underrun  in length of a section of pipe shall not be more than 10 mm/m with a maximum of 13 mm in the 
case of of an SC type pipe and 0,5%  in the case of an SI type pipe .   
7.1.6  Ogee (interlocking) ends  
The length of an ogee joint shall not exceed 50% of the wall thick ness and shall be at least (𝐷
100+7)𝑚𝑚 
where  
D is the nominal internal diameter of the pipe (in millimetres).  
Table 1 — Dimensions in mm  
1 2 3 4 5 6 7 
Nominal 
internal 
diameter  Tolerances in mm  Permissible variation in wall 
thickness max. in mm  Spigot and socket and in -the-wall joints  
SC type  SI type  SC type  SI type  Tolerance on 
stated internal 
diameter of 
spigot and male 
end of in -the-
wall joint  Tolerance on stated 
internal diameter of 
spigot and female 
end of in -the-wall 
joint  
300 ± 8 ± 6 10 6 ± 1,5 +1,5 
-1,0 
375 ± 8 ± 6 10 6 ± 2,0  +2,0 
-1,5 450 
600 ± 10 ± 8 13 6  
 
 
± 2,5   
 
 
+2,5 
-2,0 675 
750 ± 13 ± 10 13 10 
825 
900 DRS 265: 2021  
9                ©RSB 2021 - All rights reserved  
 1050  ± 19 ± 11 16 10 
1200  
1350  ± 3,0  +3,0 
-2,5 1500  
1800  
 
7.2 Resistance to proof load  
When a pipe is tested in accordance with Annex A, it shall be capable of withstanding, without the development 
of any crack of width exceeding 0.3 mm.   
7.3 Ultimate load  
The ultimate load (i.e. the maximum load that the pipe can wit hstand) shall be at least 1.25 times the appropriate 
proof load given in table 2.  
Table 2 — Proof load  
Nominal internal 
diameter  Load on effective length of pipe kN/m   
D-load1  
mm  25D  50D  75D  100D  
300  
375  
450  –  
–  
11.3  15.0  
18.8  
22.5  22.5  
28.1  
33.8  30.0  
37.5  
45.0  
525  
600  
675  13.1  
15.0  
16.9  26.3  
30.0  
33.8  39.4  
45.0  
50.6  52.5  
60.0  
67.5  
750  
825  
900  18.8  
20.6  
22.5  37.5  
41.3  
45.0  56.3  
62.0  
67.5  75.0  
82.5  
90.0  
1 050  
1 200  
1 350   26.3  
30.0  
33.8  52.5  
60.0  
67.5  78.8  
90.0  
101.3   105.0  
120.0  
135.0   
1 500  
1 800   37.5  
45.0  75.0  
90.0  112.5  
135.0   150.0  
180.0   
1) The D -load (diameter -crushing load) designation of a pipe is derived from the load, in kilonewtons , that a 1 -m length pipe can 
withstand (without the development of cracks of width exceeding the value specified in 7.2 divided by the nominal internal 
diameter of the pipe, in metres, e.g. if a load of 60 kN /m of its effective length on a pipe of nominal  internal diameter 1 200 
mm produces cracks of width not exceeding the value specified in 7.2, the D -load designation of the pipe is 50 D.   
©RSB 2021  - All rights reserved                  10 
 7.4 Resistance to hydraulic pressure (SI types pipes)  
When tested in accordance Annex C, a n SI type pipe shall withstand for at  least 2 min, an internal hydraulic 
pressure of 140  kPa without showing any sign of leakage.  
7.5 Finish of pipes  
All surfaces and edges of a pipe shall be acceptably free from imperfections that could impair the serviceability 
of the pipe. Cra ze cracks of a superficial nature and hair cracks of depth not exceeding one -third of the wall 
thickness shall be permissible.  
NOTE  Unless otherwise required, a pipe may have lifting holes (to facilitate handling and laying).  
7.6 Joints  
The joints shall be of such design and the ends of the concrete pipe sections so formed that when 
the sections are laid together they will make a continuous line of pipe with a smooth interior free 
from appreciable irregularities in the flow line.    
7.7 Test specimens   
The specif ied number of pipe required for the tests shall be furnished without charge by the manufacturer and 
shall be selected at random by the owner, and shall be pipe that would not otherwise be rejected under this 
specification. The selection shall be made at th e point or points designated by the owner when placing the order.  
7.7.1  Compression testing of cylinders  
At least five test cylinders from a group (one day’s production) of pipe sections shall be prepared for testing.   
7.7.2  Acceptability on the basis of cylinder t est results  
7.5.2.1  When the compressive strengths of all cylinders tested for a group are equal to or greater than the 
required concrete strength, the compressive strength of concrete in the group of pipe sections shall be accepted.  
7.5.2.2  When the ave rage compressive strength of all cylinders tested is equal to or greater than the 
required concrete strength, and not more than 10 % of the cylinders tested have a compressive strength less 
than the required concrete strength, and no cylinder tested has a compressive strength less than 80 % of the 
required concrete strength, then the group shall be accepted.  
7.7.3  Compression testing of cores  
7.5.3.1  The compressive strength of the concrete in the pipe shall be determined by making crushing tests 
of cores cut from the pipe.  
7.5.3.2  A core drill shall be used for securing cylindrical core specimens from the wall of the pipe; a shot 
drill or a diamond d rill shall be used.  DRS 265: 2021  
11                ©RSB 2021 - All rights reserved  
 7.5.3.3  A core specimen for the determination of compressive strength shall have a diameter at least three 
times the maximum size of the coarse aggregate used in the concrete. If cores are cut from the wall of the pipe 
and tested, the length to diameter ratio shall lie between one and two after the curved surfaces have been 
removed from the cut core.  
7.7.4  Number of cores  
One core shall be taken from a pipe section selected at random from each day’s production run of a single 
concrete stren gth.  
7.7.5  Acceptability on the basis of core test results  
7.5.5.1  When the compressive strengths of cores tested for a group of pipe sections is equal to or greater 
than the required concrete strength, the compressive strength of the concrete for the group is  acceptable. 
Concrete represented by core tests shall be considered acceptable if:   
a) the average of three cores is equal to at least 85 % of the required strength, and   
b) no single core is less than 75 % of the required strength.  
7.5.5.2  If the compressive  strength of the core tested is less than the required concrete strength, the pipe 
section from which that core was taken may be  recored. If the compressive strength of the recore is equal to or 
greater than the required concrete compressive strength, the compressive strength of the concrete for the group 
is acceptable.  
7.5.5.3  If the compressive strength of the  recore is less than the required concrete strength, the pipe section 
from which the core was taken shall be rejected. Two pipe sections from the r emainder of the group shall be 
selected at random and one core shall be taken from each pipe section. If the compressive strength of both 
cores is equal to or greater than the required concrete compressive strength, the concrete compressive strength 
of the  remainder of the group shall be acceptable. If the compressive strength of either of the two cores tested 
is less than the required concrete compressive strength, then the remainder of the group shall be either rejected 
or, at the option of the manufactur er, each pipe section of the remainder shall be cored and accepted 
individually, and any of the pipe sections that have a core with less than the required concrete compressive 
strength shall be rejected.  
7.7.6  Plugging core holes  
7.5.6.1  Core holes shall be pl ugged and sealed by the manufacturer in a manner such that the pipe section 
shall meet all of the requirements of this specification.  
7.5.6.2  Pipe sections so plugged and sealed shall be considered satisfactory for use.  
7.7.7  Absorption  
An absorption test sha ll be performed for each mix design for each production process. The absorption of a 
sample from the wall of the pipe shall not exceed 9 % of the dry mass. Each sample shall have a minimum 
mass of 1.0 kg, shall be free of visible cracks, and shall represen t the full wall thickness of the pipe. When the 
initial absorption sample from a pipe fails to conform to this specification, the absorption test shall be made on 
another sample from the same pipe and the results of the retest shall be substituted for the original test results.   
©RSB 2021  - All rights reserved                  12 
 7.7.8  Retests of pipe  
When not more than 20 % of the concrete specimens fail to pass the requirements of this specification, the 
manufacturer may cull the project stock and may eliminate whatever quantity of pipe desired and shall mark 
those pipes so that they shall not be shipped. The required tests shall be made on the balance of the order and 
the pipe shall be accepted if they conform to the requirements of this specification.  
7.7.9  Repairs  
Pipe may be repaired, if necessary, because of imp erfections in manufacture or damage during handling and 
shall be acceptable if, in the opinion of the owner, the repaired pipe conforms to the requirements of this 
specification.  
8 Inspection  
The quality of materials, the process of manufacture, and the fi nished pipe shall be subject to inspection and 
approval by the client.  
9 Rejection  
Pipe shall be subject to rejection on account of failure to conform to any of the specification requirements. 
Individual sections of pipe may be rejected  because of any of the following:  
a) fractures or cracks passing through the wall, except for a single end crack that does not exceed the depth 
of the joint;  
b) defects that indicate proportioning, mixing, and molding not in compliance with 6.2 or surface defe cts 
indicating honey combed or open texture that would adversely affect the function of the pipe;  
c) damaged or cracked ends where such damage would prevent making a satisfactory joint; and  
d) any continuous crack having a surface width of 0.3 mm or more and e xtending for a length of 300 mm or 
more, regardless of position in the wall of the pipe, for pipe not installed or under load.  
10 Marking  
10.1 The following information shall appear in legible and durable marking on each pipe in a position such that 
it cann ot be covered by a joint:  
a) the manufacturer's name or trade name or trade mark;  
b) the nominal internal diameter;  
c) the D -load designation;  
d) the date of manufacture; and  DRS 265: 2021  
13                ©RSB 2021 - All rights reserved  
 e) the word “TOP” or “BOTTOM”, or both, in the appropriate position(s) if elliptically plac ed reinforcement is 
used.  
10.2 Markings shall be indented on the pipe section or painted thereon with waterproof paint.   
©RSB 2021  - All rights reserved                  14 
 Annex  A 
(normative)  
 
Methods of testing the resistance to proof load  
A.1 Apparatus  
A.1.1  Bearers  
Two unyielding bearers of width 150 mm and having (on the inner surfaces) rubber packing pieces of width 150 
mm and of thickness 25 mm (see figure 2). Alternatively, three unyielding bearers (with rubber packing pieces 
of thickness 25 mm) of the shape and positioned as shown in figure 3. In both cases, the length of the bearers 
and of the packing is at least equal to the effective length of the pipe to be tested where, in the case of a spigot 
and socket pipe, then effective length is, for the purpose of the  test, the length of the plain cylindrical portion of 
the pipe. The hardness of the rubber is 55 IRHD ± 5 IRHD.  
A.1.2  Gauge  
A gauge made from a steel leaf, of thickness 0.25 mm and of width 10 mm and tapered (1 in 4) to a rounded 
end of width 2 mm (measured at  a line scribed at right angles to its longitudinal axis at a position 2 mm from the 
tapered end (see figure A.3).  
A.2 Procedure  
A.2.1   Place the pipe under test between, and with its longitudinal axis parallel to, the bearers.  
A.2.2   So apply an increasing  load to one bearer that the load is applied uniformly over the whole effective 
length of the pipe at a rate not exceeding 150 N/m of effective length per second.  
A.2.3   Continue until the appropriate proof load (based on the effective length of the pipe) is reached.  
A.2.4  Then, without removing or increasing the load, use the gauge to determine the width of any cracks in 
the pipe. Deem the pipe to have failed the test if  any crack is so wide that the point of the gauge can, without 
being forced, penetrate to a depth of 2 mm at close intervals over a distance of 300 mm or more.  
  
Figure A.1 — Two-bearer proof load test arrangement  
DRS 265: 2021  
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Figure A.2 — Three -bearer proof load  test arrangement  
  
Figure A.3 — Geometric relationships of cracks  
 
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Figure A.4 — Crack measuring gauge  
 
 
DRS 265: 2021  
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 Annex  B 
(normative)  
 
Method of testing ultimate load  
Immediately after checking the pipe for cracks (if any) in the test given in Annex A, increase the  load (at the rate 
used in that test) until the pipe fails or until a load of at least 1.25 times the appropriate proof load (see 7.3) is 
reached, whichever occurs first.  
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
  
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 Annex  C 
(normative)   
Hydraulic test (SI Type pipes)  
C.1 Preparation of test  specimen  
Test the pipe in the air -dry condition or after it has been soaked in water, but ensure that the surfaces of the 
pipe are dry when the pipe is tested.  
NOTE  If a pipe fails when tested in the air -dry condition, it may be soaked in water and the re tested.  
C.2 Procedure  
a) Use machined test heads having dimensions and profiles such that they match the ends of the pipe under 
test and are capable of sealing, or use any other suitable method of sealing the ends of the pipe.  
b) Connect the pipe (through the  closure at one end) to a suitable source of hydraulic pressure. Fill the pipe 
with water and ensure that all the air has been removed from the pipe.  
c) Apply pressure at a rate not exceeding 70 kPa/5 s, until a test pressure of 140 kPa has been reached.  
d) Maintain this test pressure for 2 min and then examine the pipe for signs of leakage.  
NOTE  Regard as leakage any drops forming on the surface and subsequently running or falling away from the point of 
formation.  
 
 
 DRS 265: 2021  
19                ©RSB 2021 - All rights reserved  
 Bibliography  
RS 265: 2015, Precast reinforced concrete pipe culvert — SpecificationDRS 265: 2021  
 
Price based on 1 8 pages  
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