PUBLIC REVIEW DRAFT DRAFT UGANDA STANDARD  
  DUS EAS 426-4 
First  Edition  
2016-mm-dd 
 
 Reference number  
DUS EAS 426-4: 2006 
© UNBS 201 6 
  
Concrete pipes and ancillary concrete products — Part 4: 
Specification for pre-stressed non-pressure pipes and fittings 
with flexible joints  
 PUBLIC REVIEW DRAFTDUS EAS 426-4: 2006 
ii                © UNBS  2016  - All rights reserved 
 Compliance with this standard does not, of itself confer immunity from legal obligations  
A Uganda Standard does not purport to include all necessary provisions of a contract. Users are 
responsible for its correct application  
© UNBS 2016 
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilised in any 
form or by any means, electronic or mechanical, including photocopying and microfilm, without prior written 
permission from UNBS. 
Requests for permission to reproduce this document should be addressed to 
The Executive Director 
Uganda National Bureau of Standards 
P.O. Box 6329 
Kampala 
Uganda 
Tel: 256 417 333 2 50/1/2/3 
Fax: 256 414 286 123 
E-mail: info@unbs.go.ug  
Web: www.unbs.go.ug  
 PUBLIC REVIEW DRAFTDUS EAS 426-4:2006 
© UNBS  2016 - All rights reserved                iii National foreword 
Uganda National Bureau of Standards (UNBS) is a parastatal under the Ministry of Trade, Industry and 
Cooperatives established under Cap 327, of the Laws of Uganda, as amended.  UNBS is mandated to co-
ordinate the elaboration of standards and is  
(a) a member of International Organisation for Standardisation (ISO) and  
(b) a contact point for the WHO/FAO Codex Alimentarius Commission on Food Standards, and  
(c) the National Enquiry Point on TBT Agreement of the World Trade Organisation (WTO). 
The work of preparing Uganda Standards is carried out through Technical Committees. A Technical 
Committee is established to deliberate on standards in a given field or area and consists of representatives of 
consumers, traders, academicians, manufacturers, government and other stakeholders. 
Draft Uganda Standards adopted by the Technical Committee are widely circulated to stakeholders and the 
general public for comments. The committee reviews the comments before recommending the draft standards 
for approval and declaration as Uganda Standards by the National Standards Council.  
This Draft Uganda Standard, DUS EAS 426-4: 2006 , Concrete pipes and ancillary concrete products — Part 
4: Specification for pre-stressed non-pressure pipes and fittings with flexible joints,  is identical with  and has 
been reproduced from an East African Standard, EAS 426-4 : 2006, Concrete pipes and ancillary concrete 
products — Part 4 : Specification for pre-stressed non-pressure pipes and fittings with flexible joints,  and is 
being proposed for adoption as a Uganda Standard. 
This standard was developed by the Building and civil engineering Standards Technical Committee (UNBS/TC 
3). 
Wherever the words, “ East African Standard" appear, they should be replaced by "Uganda Standard." 
 
  PUBLIC REVIEW DRAFTEAS 426-4:2006 
ICS 91.140.80 
HS 6810.20.00 
HS 6810.91.00 
  
 
© EAC 2006 First Edition 2006 
 
  
  
 
EAST AFRICAN STANDARD 
 
Concrete pipes and ancillar y concrete products — 
Part 4:  
Specification for prestressed non- pressure pipes and fittings with 
flexible joints  
  
 
    
 
  
 
 
 
 
 
  
 
 
 
 
 
EAST AFRICAN COMMUNITY  
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
ii © EAC 2006 — All rights reserved  
Table of contents 
 
1 Scope ........................................................................................................................ ..................1 
2 Normative references......................................................................................................... ..........1 
3 Terms and definitions........................................................................................................ ...........2 
4 Symbols...................................................................................................................... .................4 
5 General requirements ......................................................................................................... .........5 
5.1 Application................................................................................................................ ...........5 
5.2 Prestressing wire.......................................................................................................... .......5 
5.4 Finish (4.3.2) ............................................................................................................. ..........7 
5.5 Geometrical characteristics (4.3.3). .....................................................................................7 
5.6 Durability of joints (4.3.4.2).... ......................................................................................... .....8 
5.7 Crushing strength (4.3.5).................................................................................................. ...8 
5.8 Bends (4.3.3.3)............................................................................................................ ........8 
6 Special requirements ......................................................................................................... ..........9 
6.1 Core pipe.................................................................................................................. ...........9 
6.2 Circumferential prestressing..............................................................................................1 0 
6.3 Cover coat................................................................................................................. ........10 
7 Conformity evaluation ........................................................................................................ ........11 
7.1 Application................................................................................................................ .........11 
7.2 Prestressing wire.......................................................................................................... .....11 
7.3 Water absorption (6.7)..................................................................................................... ..12 
7.4 Geometrical characteristics ...............................................................................................1 2 
7.5 Crushing strength (Annex C) .............................................................................................12 
7.6 Prestressing and reinforcement (6.3) ................................................................................12 
7.7 Process control cubes or cylinders (7 .2.3 and G.9) ...........................................................12 
7.8 Cover coat thickness ....................................................................................................... ..13 
7.9 Cover coat bond............................................................................................................ ....13 
8 Marking...................................................................................................................... ................13 
Annex A (informative) Information to be supplied in an enquiry or order ............................................14 
Annex B (informative) Standards relevant to  CD/K/60/2004...............................................................15 
Annex C (normative) Supplementary provisions fo r prestressing wire................................................16 
Annex D (normative) Surface finish tests....................................................................................... .....23 
Annex E (normative) Dimensional tests.. ........................................................................................ ....25 
 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved iii  
Foreword 
 
Development of the East African Standards has been necessitated by the need for harmonizing requirements governing quality of products and services in East Africa. It is envisaged that through 
harmonized standardization, trade barriers which are encountered when goods and services are 
exchanged within the Community will be removed.   
In order to achieve this objective, the Partner States in the Community through their National Bureaux 
of Standards, have established an East African Standards Committee.  
The Committee is composed of representatives of the National Standards Bodies in Partner States, 
together with the representatives from the private sectors and consumer organizations. Draft East 
African Standards are circulated to stakeholders through the National Standards Bodies in the Partner 
States. The comments received are discussed and incorp orated before finalization of standards, in 
accordance with the procedures of the Community.  
East African Standards are subject to review, to keep pace with technological advances. Users of the 
East African Standards are therefore expected to ensu re that they always have the latest versions of 
the standards they are implementing.  
 
© East African Community 2006 — All rights reserved
* 
East African Community  P O Box 1096  
Arusha 
 
Tanzania  
Tel: 255 27 2504253/8 
Fax: 255-27-2504481/2504255 
E-Mail: eac@eachq.org  
Web: www.each.org 
[Based on BS 5911-5:2004] 
 
 
 
 
                                                 
* © 2005 EAC — All rights of exploitation in any form and by any means reserved worldwide for EAC Partner States’ NSBs.  
 PUBLIC REVIEW DRAFTPUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  1  
Concrete pipes and ancillar y concrete products — 
Part 5:  
Specification for prestressed non- pressure pipes and fittings with 
flexible joints 
 
 
1 Scope  
 
This part of BS 5911 specifies requirements and describes test methods for prestressed concrete 
non-pressure circular pipes and fittings with flexible joints (with seals either integrated in the units or 
supplied separately) and nominal sizes not exceeding DN 3200, for which the main intended use is the conveyance of sewage, rainwater and surface water under gravity or occasionally at low head of 
pressure, in pipelines that are generally buried. 
 BS EN 752-2, BS EN 752-3 and BS EN 752-4, BS EN 1295-1 and BS EN 1610 deal with the 
planning, design, installation and testing of drains and sewers. 
 
2 Normative references 
 
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) applies. 
 BS 146 , Specification for blastfurnace cements with strength properties outside the scope of EAS 18-
1. 
 
BS 3123 , Specification for spring calipers and spring dividers. 
 
BS 3892-1 , Pulverized-fuel ash — Part 1: Specification for pulverized-fuel ash for use with Portland 
cement. 
 
BS 4027 , Specification for sulfate-resisting Portland cement. 
 
BS 4035 , Specification for linear measuring instruments for use on building and civil engineering 
constructional works — Steel measuring tapes, steel bands and retractable steel pocket rules. 
 
BS 4449 , Specification for carbon steel bars for the reinforcement of concrete. 
 BS 4482 , Specification for cold reduced steel wi re for the reinforcement of concrete. 
 
BS 4483 , Specification for steel fabric for the reinforcement of concrete. 
 
BS 4484-1 , Specification for measuring instruments for constructional works — Part 1: Metric 
graduation and figuring of instruments for linear measurement.  BS 5204-1 , Specification for straightedges — Part 1: Cast iron straightedges (bow-shaped and I-
section).  BS 5204-2 , Specification for straightedges — Part 2: St eel or granite straightedges of rectangular 
section.  
BS 5896:1980 , Specification for high tensile steel wire and strand for the prestressing of concrete. 
 
BS 6699 , Specification for ground granulated blastfurnace slag for use with Portland cement. 
 EAST AFRICAN STANDARD PUBLIC REVIEW DRAFTEAS 426-4:2006  
2 © EAC 2006 — All rights reserved EAS 18-1 , Cement — Part 1: Composition, specificat ions and conformity criteria for common 
cements. 
 
BS EN 206-1:2000 , Concrete — Part 1: Specification, performance, production and conformity. 
 
BS EN 681-1 , Elastomeric seals — Material requirements for pipe joint seals used in water and 
drainage applications — Part 1: Vulcanized rubber. 
 
BS EN 934-2 , Admixtures for concrete, mortar and grout — Part 2: Concrete admixtures — 
Definitions, requirements, conformity, marking and labelling. 
 
BS EN 1008 , Mixing water for concrete — Specification for sampling, testing and assessing the 
suitability of water, including water recovered from processes in the concrete industry, as mixing 
water for concrete. 
 
BS EN 1916 , Concrete pipes and fittings, unreinforced, steel fibre and reinforced. 
 BS EN 12620:2002 , Aggregates for concrete. 
 
BS EN 12390-2 , Testing hardened concrete — Part 2: Making and curing specimens for strength 
tests. 
 
BS EN 12390-3 , Testing hardened concrete — Part 3: Testing hardened concrete. Compressive 
strength of test specimens. 
 
3 Terms and definitions 
 For the purposes of this part of BS 5911, the terms and definitions given in BS EN 1916 and the 
following apply. 
 
3.1 cementitious content 
amount of cement plus any pozzolanic or latent hydraulic addition in the concrete mix 
 
3.2 
core pipe pipe that is structurally reinforced with non-te nsioned steel, or longitudinally prestressed with 
pretensioned high tensile steel wire, or a combination of both, embedded in the concrete (see Figure 1) 
 
3.3 
cover coat layer of cement/fine aggregate mortar applied to the outside of a circumferentially prestressed core 
pipe (see Figure 1) 
 
3.4 
manufacturing diameter 
diameter of a unit that a manufacturer seeks to achieve 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  3 
 
 
Key 
1 High tensile steel wires for longitudinal prestressing, or mild steel reinforcement cage 
4 Longitudinal wire anchor 
2 Cover coat 5 Elastomeric seal 
3 High tensile steel wires for circumferential prestressing 6 Concrete core 
 
Figure 1 — Typical section of a prestressed concrete pipe with a spigot and socket joint 
 
3.5 
prestressed concrete pipe 
core pipe that is circumferentially prestressed to withstand design loads for the installed condition and 
is protected by a cover coat  
NOTE A typical section through a prestressed concrete pipe with spigot and socket joint is shown in Figure 1. 
 
3.6 
slurry coat 
coat of cement and water sprayed over a core pipe and circumferential prestressing wire before 
application of the cover coat 
 
3.7 
splay pipe 
prestressed concrete pipe formed with either the socket or the spigot off-set at an angle to its longitudinal axis (see Figure 2) 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
4 © EAC 2006 — All rights reserved 
 
b) Typical splay pipe (spigot) 
 
 
Key 
1 Effective length of splay pipe 2 Nominal angle 
 
Figure 2 — Typical splay pipes 
 
4 Symbols 
 
The meanings of symbols used in this part of BS 5911 shall be as given in Table 1, together with those in CD/K/60/2004, Table 2.  
Table 1 — Symbols 
 
Symbol Meaning Unit Reference 
wD  Nominal diameter of prestressing wire mm C.3.2 and C.3.3 
sh Height of studs on straightness gauge mm E.3.2.1 
'l Internal barrel length minus 0.1 m m E.3.2.1 
  PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  5 5 General requirements 
 
NOTE The numbers in parentheses after subclause headings are the corresponding subclause numbers in CD/K/60/2004. 
 
5.1 Application 
 
Except where otherwise prescribed, the requirements of this part of BS 5911 shall be in addition to 
those specified in BS EN 1916 for reinforced concrete pipes and, for the purposes of the latter, the 
reference specifications shall be those listed in Annex B of this standard.  
5.2 Prestressing wire 
 
Wire for prestressing a core pipe shall be cold-drawn high tensile steel wire, straightened and stress relieved, conforming to BS 5896:1980, Section Two and Annex C of this standard. 
 
5.3 Concrete (4.2) 
 5.3.1 Types of cement 
 
The cement (see CD/K/60/2004, 4.1) shall either: 
 
a) be factory-produced by the cement manufacturer and conform to one of the following standards as 
appropriate: 
 
Type of cement Standard 
CEM I  EAS 18-1 
CEM II/B-V  EAS 18-1 
BIII/B  BS 146 
sulfate-resisting Portland  BS 4027; or 
 
b) consist of a combination of cement conforming  to CEM I as specified in EAS 18-1 and an addition 
in the form of ground granulated blastfurnace slag (ggbs) or pulverized-fuel ash (pfa) in the 
proportions specified in 5.3.2.1 , to be included as part of the concrete mix by simultaneously 
combining them with the other concrete materials at the concrete mixer. 
 
In all cases where combinations of cement conforming to CEM I as specified in EAS 18-1 and ggbs or pfa are used, the relevant proportion of ggbs or pfa shall be fully documented in the production records.  5.3.2 Cementitious content (4.2.4) 
 
5.3.2.1 Core pipe 
 
The fully compacted concrete shall have a minimum cementitious content of not less than the relevant 
amount shown in Table 2. The composition/specificat ion of cement groups shall be as shown in Table 
3. 
 
5.3.2.2 Slurry coat 
 
The slurry coat shall consist of one part by mass of water mixed with 1.5 to 1.6 parts by mass of 
Portland cement.  5.3.2.3 Cover coat 
 
The cover coat mortar shall consist of one part by mass of Portland cement mixed with not more than 
three parts by mass of fine aggregate conforming to BS EN 12620 designation 0/4 (CP), category 
GF85 and have a water/cement ratio not greater than 0.35.  5.3.2.4 Cement compatibility 
 
Cement conforming to BS 4027 shall not be used with any other cement within the same unit. 
 
5.3.3 Chloride content (4.2.5) 
 
The calculated chloride ion content of the concrete, mortar or slurry mixes shall not exceed 0.1 % by mass of their respective cementitious contents. PUBLIC REVIEW DRAFTEAS 426-4:2006  
6 © EAC 2006 — All rights reserved  
Table 2 — Cementitious content a 
 
Class b  Aggregate carbonate 
range c Cement or combination group Minimum cement or combination content 
kg/m
3 Maximum w/c ratio 
DC-2  A, B, C  1, 2, 3  340  0.45 
A  2a  400  0.40 
A  2b, 3  380  0.45 DC-3  
B, C  2, 3  340  0.45 
DC-3*  B  2, 3  380  0.45 
DC-3* *  C  2, 3  380  0.45 
A  2a  400  0.35 
A  2b, 3  400  0.40 
A  2, 3  380  0.33 
B, C  2, 3  380  0.45 DC-4  
B, C  2, 3  360  0.40 
B  2, 3  380  0.33 DC-4*  
B  2, 3  400  0.40 
C  2, 3  380  0.33 DC-4* *  
C  2, 3  400  0.40 
A  2b, 3  380  0.33 
A  2b, 3  400  0.40 
B  3  400  0.40 
B, C  3  360  0.40 DC-4m  
B, C  3  380  0.45 
DC-4m*  B  3  380  0.33 
C  3 380 0.33 DC-4m* *  
C  3  400  0.40 
a The table is consistent with the provisions of BS 8500-1:2002 and BRE Special Digest 1 [1] insofar as they relate to 
precast concrete pipeline systems, except that the maximum water/cement (w/c) ratio is limited to 0.45 in accordance with 
CD/K/60/2004, 4.2.3.2 . 
b The class designations are those for design chemical class (DC-class) in cd/k/58-1/2004, Table A.15. Where there is 
more than one option in a class the choice is at the manufacturer’s discretion. 
c See BRE Special Digest 1 - Part 4, Table 4. 
 
Table 3 — Cement or combination groups a 
 
Type (see 5.2.1.1 ) Designation  Standard  Grouping with 
respect to sulfate 
resistance 
Portland cement CEM I EAS 18-1  1 
Portland fly ash cements CEM II/B-Vb EAS 18-1 2ac 
Sulfate-resisting Portland cement SRPC BS 4027  3 
Blastfurnace slag cementse BIII/Bd BS 146  2be 
Combinations conforming to CD/K/58-2/2004, Annex A manufactured in the concrete mixer from Portland cement and pfa or ggbs:     
CEM I cement conforming to EAS 18-1 with a mass fraction of 6 % to 20 % of combination of pfa conforming to BS 3892-1 CIIA-V  CD/K/58-
2/2004  1 
CEM I cement conforming to EAS 18-1 with a mass fraction of 21 % to 35 % of combination of pfa conforming to BS 3892-1 CIIB-Vb CD/K/58-
2/2004  2ac 
CEM I cement conforming to EAS 18-1 with a mass fraction of 36 
% to 55 % of combination of pfa conforming to BS 3892-1 CIVB-Vb CD/K/58-
2/2004  2af 
CEM I cement conforming to EAS 18-1 with a mass fraction of 6 % 
to 35 % of combination of ggbs conforming to BS 6699 CII-Sg CD/K/58-
2/2004  1 
CEM I cement conforming to EAS 18-1 with a mass fraction of 36 % to 65 % of combination of ggbs conforming to BS 6699 CIIIA CD/K/58-
2/2004  1 
CEM I cement conforming to EAS 18-1 with a mass fraction of 66 
% to 80 %e of combination of ggbs conforming to BS 6699 CIIIBd CD/K/58-
2/2004 2be 
a The table is consistent with BS 8500-1:2002, Table A.17 and CD/K/58-2/2004, Table 1. 
b Where the proportions for sulfate resistance are required, i.e. not less than 25 % and not more than 40 % pfa, add to the 
 abbreviation “+SR”. 
c Provided the pfa content is a mass fraction of not less than 25 % of cement or combination. Where it is less than 25 %, 
 the cement of combination falls within group 1. 
d Where the proportions for sulfate resistance are required (see e), add to the abbreviation “+SR”. 
e Where the alumina content of the slag exceeds 14 %, the tricalcium aluminate content of the Portland cement fraction 
 should not exceed 10 %. Where this is not the case, the grouping with respect to sulfate resistance is “1”. 
f Provided the pfa content is a mass fraction of not more than 40 % of cement or combination. Where it exceeds 40 %, no 
 guidance is provided. 
g Where necessary, this class can be subdivided into CIIA-S (6 % to 20 % ggbs) and CIIB-S (20 % to 35 % ggbs). 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  7  
5.4 Finish (4.3.2) 
 
5.4.1 Surface evenness  
When tested in accordance with D.1, the internal surface of a unit shall not have irregularities that 
cause the central portion of the gauge to touch the unit. 
 
5.4.2 Surface voids 
 
When tested in accordance with D.2 surfaces of units shall be free from voids that permit diametrically opposite points of the rim of the gauge to touch the surface of the unit simultaneously. 
 
Units exhibiting any surface void greater than 12 mm deep shall be deemed not to conform to this part of BS 5911. 
 
NOTE Voids up to and including 12 mm deep may be made good by the manufacturer — see CD/K/60/2004, 4.3.2 . 
 5.4.3 Surface cracking  
In addition to the requirements of CD/K/60/2004, 4.3.2 and 6.3.4 of this part of BS 5911, the surface 
width of any circumferential crack in a core pipe due to discontinuity of prestress at the spigot end 
shall not exceed 0.1 mm. 
 
5.5 Geometrical characteristics (4.3.3) 
 
5.5.1 General 
 
Subject to the requirements of this clause, the internal diameter and core pipe wall thickness of units, 
and the configuration of splay pipes and bends, shall conform to those stated in the factory documents. 
 
5.5.2 Nominal sizes  
NOTE Nominal size is defined in CD/K/60/2004, 3.1.16 as a numerical designation of the size of a unit, which is a 
convenient integer approximately equal to the manufacturing dimension in millimetres; for a circular unit it is the internal 
diameter (DN). 
 
The nominal sizes of units shall be those given in Table 4. 
 
5.5.3 Internal manufacturing diameters 
 
The manufacturer shall make available, at the enquiry stage, information on the internal 
manufacturing diameters of units that can be supplied (see Annex A).  
The internal manufacturing diameters of units shal l be not outside the limits given in Table 4. 
 
5.5.4 Dimensional tolerances 
 
5.5.4.1 Tolerances on internal diameter 
 
The tolerance on the internal manufactured diameter of a unit shall be ±(3 + 0.005DN) mm, limited to 
±15 mm (see Table 4). No individual measurement, measured in accordance with E.1 shall be outside 
the specified limits.  
5.5.4.2 Tolerances on core pipe wall thickness  
Any value of core pipe wall thickness measured in accordance with E.2 shall be not less than the 
value stated in the factory documents.  
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
8 © EAC 2006 — All rights reserved 5.5.4.3 Deviation from internal straightness 
 
When measured in accordance with E.3, both ends of the gauge shall not make contact with the 
internal surface of a straight unit when using Edge X and the two studs shall be in contact 
simultaneously with that surface when using Edge Y.  Table 4 — Nominal sizes, internal manufac turing diameters and tolerances of units 
 
Limits of internal manufacturing 
diameter 
mm Tolerance on internal manufactured 
diameter  
mm Nominal size  
 
DN 
Minimum  Maximum  Internal  
450  440  460  ±5  
500  490  525  ±6  
600  580  610  ±6  
700  675  720  ±7  
800  770  825  ±7  
900  875  950  ±8  
1000  980  1 070  ±8  
1200  1 180  1 220  ±9  
1400  1 350  1 420  ±10  
1500  1 470  1 530  ±11  
1600  1 580  1 675  ±11  
1800  1 780  1 830  ±12  
2000  1 950  2 135  ±13  
2200  2 170  2 250  ±14  
2500  2 375  2 550  ±15  
2800  2 680  2 850  ±15  
3000  2 965  3 050  ±15  
3200 3165 3250 ±15 
NOTE Classic sizes, denoted by an asterisk, will be phased out if called for by further harmonization.  
 5.5.4.4 Squareness of ends 
 Units other than splay pipes shall be capable of being jointed in any orientation with their axes 
coincident within the deflection limit specified in CD/K/60/2004, E.5.2 . 
 
NOTE 1 Squareness of ends of units is significant only to the extent that it relates to the performance of the joint assembly. 
 NOTE 2 Information on the splay angles that can be supplied for splay pipes should be given to the purchaser on request (see 
Annex A). 
 
5.6 Durability of joints (4.3.4.2) 
 
The durability of joints shall be demons trated in accordance with CD/K/60/2004, 4.3.4.2 Method 1. 
 
5.7 Crushing strength (4.3.5) 
 
NOTE Strength class is defined in CD/K/60/2004, 3.1.19 as the minimum crushing load in kilonewtons per metre, divided by 
one thousandth of a unit's nominal size (DN). 
 Units shall be strength class 120 with corresponding minimum crushing loads in accordance with Table 5.  
Units of other crushing strength shall be permitted only if their special strength class is separated by 
at least 20 % of the next lower value and that they conform to BS EN 1916 and this part of BS 5911 in all other respects. Minimum crushing loads corresponding to special strength classes shall be 
rounded up to the nearest kilonewton per metre (kN/m). 
 
5.8 Bends (4.3.3.3) 
 
Bends shall be fabricated from cut lengths of pipe conforming to this part of BS 5911. PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  9  
For bends having subtended angles ! greater than 70°, the radius r as shown in CD/K/60/2004, Figure 
3 shall be a minimum of 0.7DN mm. 
 
NOTE Typical angles ! are 11° 15´, 22° 30´ and 45°. 
 
Table 5 — Minimum crushing loads for strength class 120 units 
 
Nominal size 
DN Minimum crushing load, Fn 
kN/m 
450*  54 
500  60 
600  72 
700  84 
800  96 
900*  108 
1000  120 
1200  144 
1400  168 
1500*  180 
1600  192 
1800  216 
2000  240 
2200  264 
2500  300 
2800  336 
3000  360 
3200 384 
NOTE 1 Classic sizes, denoted by an asterisk will be phased out if called for by further European harmonization. 
 
NOTE 2 BS EN 1295-1:1998, Table NA.5 recommends that the minimum value of safety factor for the structural design 
of reinforced pipelines should be increased from the normal 1.25 to 1.5 if, as is the case of CD/K/60/2004, the proof load 
is 67 % of the minimum crushing load. The recommendation is equally valid for prestressed non-pressure concrete pipelines.
 
 
6 Special requirements 
 
NOTE The numbers or letters in brackets after subclause headings are the corresponding subclause numbers or Annex 
designations in CD/K/60/2004. 
 
6.1 Core pipe 
 
6.1.1 Prestressing or reinforcement 
 6.1.1.1 General 
 At the manufacturer's discretion a core pipe shall either be longitudinally prestressed in accordance 
with 6.1.1.2 , or reinforced with non-tensioned steel in accordance with 6.1.1.3 . 
 
6.1.1.2 Longitudinal prestressing 
 
The core pipe shall be longitudinally prestressed thro ughout its length (including the socket) by means 
of high tensile steel wires, which shall be provided with permanent anchorages embedded in the 
concrete within the joint portion at each end. The longitudinal prestress shall be sufficient to prevent 
tensile cracks developing in the core pipe due to the combined effects of circumferential prestressing and bending due to beam loading. The longitudinal wires shall be stressed to the design tension, 
taking into account the yield or slip of the temporary anchorages on the pipe moulds, and the tension 
shall be maintained whilst curing the concrete. The tensioned wires shall not be released until the concrete in the core pipe has attained a characteristic compressive strength of 27 MPa, as 
demonstrated by process control cubes or cylinders (see 7.7), the choice being at the manufacturer's 
discretion. 
 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
10 © EAC 2006 — All rights reserved 6.1.1.3 Reinforcement 
 
As an alternative to longitudinal prestressing in accordance with 6.1.1.2 (see 6.1.1.1 ), it is permissible 
for the core pipe to be reinforced with non-tensioned steel in accordance with CD/K/60/2004, 5.2.1 , in 
order to prevent tensile cracks developing due to the combined effects of the circumferential 
prestressing and bending due to beam loading. 
 
6.1.2 Concrete cover (5.2.2) 
 
The minimum concrete cover at the end faces of a co re pipe shall be 12 mm; fo r all other surfaces of 
the core pipe it shall be 15 mm or the relevant  nominal maximum size of aggregate stated in the 
factory documents, whichever is the larger. The holes at the longitudinal wire anchors in the spigot 
and socket faces shall be plugged with mortar conforming to 5.3.2.3 , to ensure a watertight seal to the 
steel anchors. 
 
NOTE 1 Given the inspection procedures specified in this part of BS 5911 and the maximum permitted stabilized surface 
crack width specified in CD/K/60/2004, 5.2.3 the value of minimum concrete cover is consistent with the serviceability 
conditions specified in CD/K/60/2004, 4.3.8. Taken together, these factors are also consistent with the crack control provisions 
given in BS 8110-1 and BS 8110-2. 
 NOTE 2 Units conveying sea water, industrial waste, etc. and those to be installed in more aggressive serviceability conditions than those specified in CD/K/60/2004, 4.3.8 might need additional concrete cover. The advice of the pipe 
manufacturer should be sought in such a situation. 
 
6.2 Circumferential prestressing 
 
6.2.1 General 
 
Circumferential prestressing shall not take place until the concrete in a core pipe has reached sufficient compressive strength to resist without damage the forces acting upon it, which shall be not 
less than a minimum characteristic value of 35 MPa as demonstrated by process control cubes or 
cylinders (see 7.7), the choice being at the manufacturer's discretion. The compressive stress induced 
in a core pipe during prestressing shall not exceed 55 % of the characteristic compressive strength of 
the concrete in the core pipe at that time. 
 The mean tension in the circumferential prestressing wire shall be at least the design tension. Normal 
fluctuations in tension shall not deviate by more t han 10 %, nor shall more than 5 % of the windings 
have instantaneous fluctuations exceeding the 10 % deviation. 
 6.2.2 Winding 
 
Methods and equipment for applying the circumferential prestressing wire shall be: 
 
a) such that the wire is wound around the core pipe in a helical form at the design spacing stated in 
the factory documents; and 
 
b) capable of controlling and indicating the tension.  6.2.3 Spacing 
 
The clear distance between circumferential prestressing wire shall be not less than 5 mm.  6.2.4 Splicing 
 
The design of any splice to be made in prestressing wire shall be recorded in the factory documents 
and the tensile strength of all splices shall be not less than that of the wire itself. 
 
6.3 Cover coat 
 6.3.1 Preparation of external surface 
 To obtain a satisfactory bond, care shall be taken to ensure that the external surface of a core pipe is 
damp immediately before application of the slurry and cover coats. 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  11 6.3.2 Application of slurry and cover coats 
 
The slurry coat shall be sprayed over a core pipe and circumferential prestressing wires immediately 
before application of the cover coat which, premixed with water, shall then be mechanically driven at 
high velocity against the external surface of the core pipe and wires, producing a dense coating having a thickness of not less than 20 mm over all wires. For multiple layers of windings and cover 
coating, the final cover coat shall provide the 20 mm minimum cover. 
 Pneumatic processes in which the mixing of ingredie nts is carried out at the nozzle or gun shall not be 
used.  
6.3.3 Cover coat bond 
 
There shall be no debonding of the cover coat from a core pipe or circumferential prestressing wires 
in a finished product. If, on inspection, debonding is found to have taken place (see 7.9), the cover 
coat shall be removed from the defective area at least 25 mm around the area of debonding. A slurry 
coat as specified in 5.3.2.2 shall then be applied to the exposed core pipe and circumferential wire 
immediately before the cover coat repair is applied. The cover coat shall be replaced in accordance 
with 6.3.2 . 
 
6.3.4 Crushing strength 
 
The requirement in CD/K/60/2004, 5.2.3 for a maximum stabilized surface crack width of 0.30 mm 
when tested in accordance with CD/K/60/2004, 6.4 shall be amended to 0.20 mm for the purposes of 
this part of BS 5911. There shall be no cracks in the cover coat other than those permitted by 5.4.3 of 
this part of BS 5911. 
 
The requirement in CD/K/60/2004, C.4.4 for the load to be increased to the ultimate (collapse) load F
u 
shall be deemed to be met if the applied load has reached 1.10 times the minimum crushing load Fn 
without causing the pipe to collapse. 
 
NOTE For prestressed concrete non-pressure pipes, especially in the larger sizes, it is often impracticable for the apparatus 
to test the pipe to collapse. 
 
6.3.5 Conformity of proof (crack) load tested pipes 
 
Pipes tested only to proof (crack) load in accordance with CD/K/60/2004, 6.4 and meeting the 
requirements of 6.3.4 of this part of BS 5911 shall be deemed to conform to this standard. 
 
7 Conformity evaluation 
 
7.1 Application 
 
The conformity evaluation requirements of BS EN 1916 shall apply to this part of BS 5911, supplemented or qualified by the following sampling procedures.  
7.2 Prestressing wire 
 7.2.1 Sampling procedures 
 After an initial type test in each case, routine inspection of elongation, reverse torsion and resistance 
to hydrogen embrittlement shall be carried out on the basis of batches comprising each consignment of prestressing wire or, if the consignment embraces more than one casting of constituent metal, each part of the consignment relevant to a separate casting. 
 
For the elongation and reverse torsion tests, three samples shall be taken in each case from three different spools or coils of wire. For the resistance to hydrogen embrittlement test the six test cylinders 
shall be wound using wire from at least three different spools or coils. 
 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
12 © EAC 2006 — All rights reserved 7.2.2 Acceptance criteria for resistance to hydrogen embrittlement 
 
The acceptance criteria for the resistance of the prestressing wire to hydrogen embrittlement shall be 
as follows: 
 
a) if the breaking time (see C.5) for each of the six test cylinders is greater than 90 min, the batch 
shall be accepted; 
 
b) if the breaking time for one or more cylinders is less than 90 min, the test shall be repeated using 
six other cylinders; 
 c) if the mean of the breaking times for the three wo rst results in each of the two series in b) is 
greater than 90 min, the batch shall be accepted; nevertheless, if in each of the two series the 
breaking time for one or more cylinders is le ss than 60 min, the batch shall be rejected; 
 
d) if the mean of the breaking times for the three worst results in each of the two series in b) is less 
than 90 min, the batch shall be rejected. 
 
7.3 Water absorption (6.7) 
 
Samples for the purposes of CD/K/60/2004, 6.7 shall be cut from a hardened core pipe. 
 
7.4 Geometrical characteristics 
 
Sampling procedures to evaluate the conformity of internal diameter, core pipe wall thickness and internal straightness to 5.5.4.1 , 5.5.4.2 and 5.5.4.3 respectively shall be in accordance with those for 
“Geometrical characteristics — units” in CD/K/60/2004, Table H.1. 
 
7.5 Crushing strength (Annex C) 
 
For the purposes of this part of BS 5911, references in CD/K/60/2004, Annex I to the ultimate 
(collapse) load Fu in connection with reinforced concrete pipes shall be taken as references to 1.10 
times the minimum crushing load Fn where such a load has not caused a pipe to collapse; “basic” 
level inspection of crushing strength in accordance with CD/K/60/2004, I.1.1 is not permitted. 
 
7.6 Prestressing and reinforcement (6.3) 
 
The conformity of the core pipe longitudinal prestressing or reinforcement and the circumferential 
prestressing to 6.1 and 6.2 respectively shall be evaluated as for reinforcement in accordance with 
CD/K/60/2004, 6.1 and 6.3. 
 
7.7 Process control cubes or cylinders (7.2.3 and G.9) 
 
NOTE The testing of cubes or cylinders is intended as a control check at critical stages of manufacture (see 6.1.1) and not 
as an indication of the proof load crushing strength of matured units. 
 
Process control cubes or cylinders shall be made and cured either:  
a) in a manner that reflects the pipe manufacturing process; or 
 b) in accordance with BS EN 12390-2. 
 
The cubes or cylinders shall be tested in accordance with the relevant part of BS EN 12390-3, sufficient being made and tested to ensure that a core pipe has reached the required minimum 
characteristic compressive strength at the stages described in 6.1.1.2 and 6.2.1 . 
 
If the method given in b) is adopted by the manufacturer, a conversion factor shall be applied to the 
results of the tests to take into account differences between the pipe manufacturing process and that 
used to produce the test specimens in accordance with the relevant part of BS EN 12390-2 and BS EN 12390-3. PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  13  
This conversion factor shall be determined by the manufacturer by correlation tests, the results of 
which shall be made available for inspection. Correlation tests shall be repeated at least annually and 
whenever a change is made in the materials or process used to manufacture the pipes. 
 
The minimum frequency of sampling shall be in accordance with BS EN 206-1:2000, 8.2.1 . 
 
7.8 Cover coat thickness 
 
The conformity of the cover coat thickness to 6.3.2 shall be evaluated as for concrete cover in 
accordance with CD/K/60/2004, 6.1 and 6.3. 
 
7.9 Cover coat bond 
 
The cover coat bond shall be evaluated for conformity to 6.3.3 by virtue of appearance and random 
hammer ringing checks on a sample unit. The frequency of sampling shall be not less than once 
every five working days.  
8 Marking 
 
In addition to the requirements in CD/K/60/2004, Clause 8 (but excluding the requirement to mark EN 
1916) each unit shall be marked BS 5911-5. Special strength class units (see 5.7) shall also be 
marked with the relevant class. PUBLIC REVIEW DRAFTEAS 426-4:2006  
14 © EAC 2006 — All rights reserved  
Annex A (informative) Information to be supplied in an enquiry or order 
 
The following particulars cover essential details required by the manufacturer so that an enquiry or order may be fully understood: 
 
 Reference in: 
 CD/K/60/2004  CD/K/61-4/2004 
a) quantity and nominal size(s) of units ― 5.5.1 
b) any special strength class of units 4.3.5 5.7 
c) design chemical class (DC-class) of concrete in units 4.3.8 5.3.2.1 
d) if additional concrete cover is required 4.3.8 and 5.2.2 6.1.2 
e) splay angles and whether at the spigot or socket end of 
splay pipes 5.3.1 ― 
f) dimensions and materials of inlets or branch pipes for 
junctions 5.4 ― 
g) if the products are to be fully covered by a third party 
certification scheme 7.1 Foreword 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  15  
Annex B (informative) Standard s relevant to CD/K/60/2004 
 
The reference specifications prescribed in 5.1 for materials are listed in Table B.1. 
 
Table B.1 — British Standards relevant to CD/K/60/2004 
 
Reference in CD/K/60/2004 Relevant Standard 
Subclause number  Material/Characteristic  
EAS 18-1 
BS 146 4.1  Cements  
BS 4027 
4.1  Aggregates  BS EN 12620 
4.1  Mixing water  BS EN 1008a) 
4.1  Admixtures  BS EN 934-2 
BS 3892-1 4.1  Additions  
BS 6699 
BS 4449 
BS 4482 4.1  Reinforcing steel b) 
BS 4483 
4.1.2 and 4.3.3.2  Joint seals  BS EN 681-1 
a) BS EN 1008:2002, 3.1 specifies that potable water does not need testing prestressing wire, see 5.2 
b) For prestressing wire, see 5.2. 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
16 © EAC 2006 — All rights reserved  
Annex C (normative) Supplementary provisions for prestressing wire 
 
NOTE This Annex is consistent with BS EN 642:1995, Annex A. 
 
C.1 Mechanical properties 
 C.1.1 Elongation 
 
The minimum elongation of prestressing wire under the maximum load (i.e. immediately before the 
occurrence of necking) shall be 3 % of its original length when tested in accordance with the 
procedure in C.2.4.1 , or 2 % excluding any necking if tested to breaking in accordance with C.2.4.2 , 
the choice of procedure being at the manufacturer's discretion.  
C.1.2 Reverse torsion 
 
When tested in accordance with C.3 the prestressing wire shall not exhibit a visible crack until at least 
three “1 – 2 – 1” cycles (see C.3.4) of reverse torsion have been completed. 
 C.1.3 Resistance to hydrogen embrittlement 
 
When tested in accordance with C.4 and evaluated in accordance with 7.2.2 the elapsed time before 
the prestressing wire breaks as a result of hydrogen embrittlement shall exceed 90 min.  
C.2 Elongation tests 
 
C.2.1 Principle 
 
The purpose of this test is to evaluate whether the pr estressing wire conforms to either or both of the 
requirements in C.1.1 for minimum elongation. 
 C.2.2 Apparatus 
 
C.2.2.1 Mechanical equipment, capable of exerting a tensile force in excess of the specified 
characteristic breaking load of the prestressing wire and with a means of measuring that force to an 
accuracy of ±3 %. 
 
C.2.3 Preparation 
 
C.2.3.1 Elongation at maximum load 
 
The test piece comprises a length of prestressing wire such that the free section to be elongated 
under the maximum load is greater than 200 mm. 
 
C.2.3.2 Permanent elongation 
 
The test piece comprises not less than 500 mm of prestressing wire.  C.2.4 Procedure  
C.2.4.1 Elongation at maximum load 
 
Mark a reference length of 200 mm on the test piece then clamp it in the apparatus. Apply a tensile force to the wire and, for increasing values of load, measure the corresponding plastic elongations of 
the reference length. Plot the results on a load/exte nsion graph until it shows that the maximum load 
has been reached. After reducing the tensile force on the wire to zero, record the plastic elongation of 
the reference length corresponding to the maximum load. 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  17 The elongation of the reference length is the sum of the plastic elongation at the maximum load as 
determined above and the elastic elongation, which is a statistical value based on certified tests by 
the wire supplier. Record the sum of these two elongations. 
 
C.2.4.2 Permanent elongation 
 Make a series of reference marks 50 mm apart on the test piece then clamp it in the apparatus. Apply 
a tensile force to the wire and gradually increase it until the test piece breaks, then measure and record the permanent elongation of an original 100 mm reference length, chosen as being farthest 
from any necking of the wire. 
 
C.2.5 Expression of results 
 
C.2.5.1 Elongation at maximum load 
 Express the summated elongation determined in accordance with C.2.4.1 as a percentage of the 200 
mm reference length and record it.  
C.2.5.2 Permanent elongation 
 
Express the permanent elongation determined in accordance with C.2.4.2 as a percentage of the 100 
mm reference length and record it. 
 
C.3 Reverse torsion test  
C.3.1 Principle 
 
The purpose of this test is to evaluate whether the prestressing wire conforms to the requirement in 
C.1.2 for reverse torsion. 
 
C.3.2 Apparatus 
 
C.3.2.1 Mechanical equipment, able to grip a test piece of prestressing wire stretched between two 
jaws, one of which can be rotated in either direction about the longitudinal axis of the installed test 
piece at a speed not exceeding one turn per 10 seconds. The distance between the jaws is equal to 
50 times the nominal diameter Dw of the prestressing wire. 
 
C.3.3 Preparation 
 
The test piece comprises a length of prestressing wire not less than 70 times its nominal diameter D
w. 
 
C.3.4 Procedure  
Grip the test piece in the apparatus, stretched betw een the two jaws, and twist it one complete turn to 
the right about its longitudinal axis, then two turns to  the left and another turn to the right, returning to 
the initial position. These four turns constitute a full cycle of torsion, described as “1 – 2 – 1”.  
Repeat the “1 – 2 – 1” procedure until the first visible crack occurs in the test piece and record the 
number of cycles completed. 
 
C.4 Resistance to hydrogen embrittlement test 
 C.4.1 Principle 
 The purpose of this test is to evaluate whether the resistance of prestressing wire to hydrogen 
embrittlement conforms to the requirement in C.1.3 . The wire is wound at a constant tension close to 
the design value for working conditions onto small diameter test cylinders, which are then immersed 
in an acid solution whilst under cathodic polarization. This causes hydrogen to be generated and 
available for absorption by the wire. 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
18 © EAC 2006 — All rights reserved C.4.2 Apparatus 
 
C.4.2.1 Six test cylinders, each consisting of a cold drawn mild steel tube placed within a suitable 
close-fitting and isolating hard plastic sleeve and equipped with: 
 
⎯ a catch plate for applying a rotational movement whilst wrapping the prestressing wire around the 
cylinder; 
 
⎯ a clamping plate with bolts to secure the end of the wire after wrapping. 
 
Figure C.1 prescribes the test cylinder dimensions and details the accessories. One end of the wire to be tested is equipped with an anchoring device to hook it onto the cylinder. 
 
C.4.2.2 Electricity supply panel, equipped with regulating potentiometers and capable of supplying a 
direct rectified cathodic polarization current equal to 1 mA per cm2 area of immersed wire to an 
accuracy of ±10 %. 
 
C.4.2.3 Non-conducting acid-resistant circular tank, as described in Figure C.2 and with a platinum 
anode attached around its internal circumference at a height equal to half the height of test cylinder.  
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  19 Dimensions in millimetres  
 
 
Key 
1 Anchoring device     4 Steel cylinder 
2 Catch plate     5 Steel plate embedded into plastic sleeve 54 × 20 × 11 
3 Suitable, hard isolating plastic sleeve   6 2 dia 10.5 holes 
 
Figure C.1 — A test cylinder and its accessories 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
20 © EAC 2006 — All rights reserved Dimensions in millimetres  
 
 
Key 
1 Self-tightening cone situated outside the solution  5 Ring hook 2 Steel wire connected to cathode    6 Circular electrode platinum 0.6 × 0.05 mm 
3 Electrical wires connected to the circular electrode  7 Electrode positioning ring 4 Cylinder centring device     8 Rubber secting 
 
Figure C.2 — Test tank and arrangement of a test cylinder in acid solution 
 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  21 C.4.2.4 Test solution, of hydrochloric acid (containing ½ mole of acid per litre) and “pure for analysis” 
characterized by the following maximum contents of impurities: 
 
— non-volatile residue  < 0.0010 % 
— heavy metals (as lead, Pb)  < 0.0002 % 
— iron, Fe  < 0.0005 % 
— arsenic, As  < 0.0001 % 
— bromine, Br  < 0.0010 % 
— sulfate, SO 4 < 0.0002 % 
— oxidizing agents (as chloride, Cl)  < 0.0002 % — reducing agents (as sulfide, SO
2)  < 0.0010 % 
 
The solution, which is replaced for each test, is made from 20 litres of distilled water having a 
resistivity between 500 7m and 800 7m and the quantity of hydrochloric acid needed to achieve and 
maintain a normality between 0.48 and 0.52. 
 C.4.3 Preparation 
 After anchoring the end of the prestressing wire onto the first test cylinder make one helical wind, 
without tension so as to protect the anchoring device, then subject the wire to a winding tension equal 
to 75 % of its ultimate tensile strength as guaranteed by the supplier. If the guaranteed ultimate tensile strength of the wire is not known, use a winding tension equal to 70 % of its actual ultimate 
tensile strength. The tolerance on the winding tensio n shall be ±10 % of the ultimate tensile strength. 
 
Wind the wire around the cylinder at a linear speed of (40 ± 5) mm per second until seven helixes at a 
constant pitch are completed, then secure it with the clamping plate bolts so as to maintain the 
applied tension. The applied wire shall have an overall twist of at least 0.75 turns and not more than 1.5 turns. After relaxing the applied tension, cut off the loose part of the wire and make marks on both 
the applied wire and the cylinder so as to reveal any subsequent slipping. 
 Fix an electrical connection (the cathode) to the anchoring device located at one end of the applied 
wire. 
 
Figure C.3 describes a wire-wrapped test cylinder and Figure C.4 illustrates a typical arrangement for 
the winding system. On completion of the wire winding, protect the clamping plate bolts with a mastic 
compound to isolate the steel part from the acid solution. 
 
Prepare the remaining five test cylinders in the same way. 
 
C.5 Procedure 
 
Within 24 hours of winding the first test cylinder, place the acid solution in the test tank and maintain 
the former's temperature at (18 ± 2) °C. Partially immerse the cylinder in the solution, resting it on a 
rubber seating as shown in Figure C.2 and adjusting its position as necessary by means of an appropriate device. 
 
Connect the platinum anode attached around the inside of the tank and the cathode of the wire under test to the electricity supply panel, the anode being connected at three equidistant points so that the potential is the same anywhere on its circumference. Switch on the current immediately after 
immersing the cylinder and thereby induce polarization as a result of the current passing between the 
two anodes, through the acid solution. 
 
Record the elapsed time in minutes between switch ing on the current and the tensioned wire around 
the cylinder breaking as a result of hydrogen embrittlement (the “breaking time”). If the wire has not 
broken after three hours, discontinue the test and record that fact. 
 
Repeat the procedure for the remaining five test cylinders.  C.6 Expression of results 
 The test results are expressed and recorded as the breaking time (or 180 min in the case of failure to 
break within 3 h) for the prestressing wire around each of the six test cylinders.  PUBLIC REVIEW DRAFTEAS 426-4:2006  
22 © EAC 2006 — All rights reserved  
Dimensions in millimetres 
 
 
 
Key 
1 Electric wire connected to steel wire   3 Mark 
2 1 Spiral wound without tension   4 Dia. 10 bolts length = 50 
 
Figure C.3 — A wire-wrapped test cylinder 
 
Dimensions in millimetres unless stated otherwise  
 
 
Key 
1 Cylinder dia. 172    6 Cable (tension T/2) 
2 5 m of wire    7 Tension T/2 
3 Compensation hoist dia. 690  8 Tension T/2 
4 Wire (tension T)    9 Load T/2 5 Tension T/4    10 Mobile trolley for applying tension and compensation 
 
Figure C.4 — Typical arrangement for winding a test cylinder 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  23  
Annex D (normative) Surface finish tests 
 
D.1 Surface evenness test  
D.1.1 Principle  
The purpose of this test is to evaluate whether the internal surface of a unit conforms to the limiting requirement in 5.4.1 for evenness. 
 D.1.2 Apparatus  
D.1.2.1 Gauge, as described in Figure D.1. 
 
Dimensions in millimetres 
 
 
 
Figure D.1 — Gauge for assessing surface eveness 
 
D.1.3 Procedure 
 
D.1.3.1 Place the gauge in the unit so that its axis is in the same plane as the unit's longitudinal axis. 
 
D.1.3.2 Roll the gauge around the inside of the unit, taking care to ensure that its axis remains in the 
same plane as the unit's longitudinal axis at all times. 
 
D.1.4 Expression of result 
 
Record whether the gauge rolled over any part of the internal surface without the central portion of the gauge contacting the unit.  
D.2 Surface void test 
 
D.2.1 Principle  
The purpose of this test is to evaluate whether any void in the surface of a unit conforms to the limiting requirement in 5.4.2 . 
 D.2.2 Apparatus 
 
D.2.2.1 Gauge, as described in Figure D.2. 
 
D.2.3 Procedure 
 
Apply the ball of the gauge to the void and record whether diametrically opposite points in the rim of the gauge simultaneously touched the surface of the unit. 
 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
24 © EAC 2006 — All rights reserved Dimensions in millimetres  
 
 
Key 
1 Cylinder 
2 Hemisphere dia. 10 ± 0.5 
 
Figure D.2 — Gauge for assessing surface voids 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  25  
Annex E (normative) Dimensional tests 
 
NOTE At the manufacturer's discretion it is permissible to use purpose-made“go/no-go” steel gauges for dimensional 
measurements in lieu of the apparatus specified for the tests in this Annex. 
 
E.1 Internal diameter test 
 E.1.1 Principle 
 
The purpose of this test is to evaluate whether the internal diameter of a unit conforms to 5.5.4.1 . 
 
E.1.2 Apparatus 
 
E.1.2.1 Steel measuring tape or retractable pocket rule, conforming to BS 4035 with metric 
graduation and figuring conforming to BS 4484-1.  E.1.3 Procedure 
 Approximately 50 mm from each end of the bore, make three measurements of the internal diameter 
at approximately 60° to each other. 
 
E.1.4 Expression of results  
Record whether each measured value of the internal diameter conforms to 5.5.4.1. 
 
E.2 Core pipe wall thickness test  
E.2.1 Principle  
The purpose of this test is to evaluate whether the wall thickness of a core pipe conforms to 5.5.4.2 . 
 E.2.2 Apparatus 
 E.2.2.1 Outside spring caliper, conforming to BS 3123. 
 E.2.2.2 Steel measuring tape or retractable pocket rule, conforming to BS 4035 with metric 
graduation and figuring conforming to BS 4484-1. 
 
E.2.3 Procedure 
 
Measure the core pipe wall thickness at approximately 50 mm from the end of the external barrel at 
the spigot end, at three positions equidistant around the circumference of the unit. 
 
E.2.4 Expression of results 
 
Record whether each measured value of the wall thickness conforms to 5.5.4.2 . 
 
E.3 Straightness test  
E.3.1 Principle 
 
The purpose of this test is to evaluate whether the in ternal straightness of a straight unit conforms to 
5.5.4.3 . 
 
E.3.2 Apparatus 
 
E.3.2.1 Rigid straightedge, made into a gauge of the form and dimensions shown in Figure E.1. 
 
 PUBLIC REVIEW DRAFTEAS 426-4:2006  
26 © EAC 2006 — All rights reserved E.3.3 Procedure 
 
E.3.3.1 Place the straightedge in the bore with Edge X (see Figure E.1) in contact with the unit and on 
a line parallel to its longitudinal axis. Hold the plane of the gauge in a radial plane and record whether 
both ends of the gauge, wherever so placed, were in contact with the internal surface of the unit. 
 
E.3.3.2 If both ends of the gauge were not in contact with the internal surface of the unit at both ends, 
reverse the gauge so that Edge Y, placed as above (see Figure E.1), is adjacent to the internal 
surface of the unit.  E.3.4 Expression of result 
 Record whether both ends of the gauge were in contact with the internal surface of the unit when 
using Edge X, and whether the two studs (see Figure E.1) touched the surface simultaneously when 
using Edge Y.  
Dimensions in millimetres  
 
 
Key 
1 Edge Y 
2 Edge X 
 
hs = (3.5 l' ± 5 %) in mm 
 
NOTE The studs should be detachable from the basic straightedge to facilitate checking and replacement. 
 
Figure E.1 — Gauge for measuring deviation from internal straightness PUBLIC REVIEW DRAFTEAS 426-4:2006  
© EAC 2006 — All rights reserved  27  
Bibliography 
 
BS 5911-1:2002, Concrete pipes and ancillary concrete products — Part 1: Specification for 
unreinforced and reinforced concrete pipes (including jacking pipes) and fittings with flexible joints (complementary to CD/K/60/2004). 
 
BS 5911-100:1988, Concrete pipes and ancillary conc rete products — Part 100: Specification for 
unreinforced and reinforced pipes and fittings with flexible joints.1) 
 
BS 8110-1:1997, Structural use of concrete — Part 1: Code of practice for design and construction.  
BS 8110-2:1985, Structural use of concrete — Part 1: Code of practice for special circumstances. 
 
BS 8500-1:2002, Concrete — Complementary British Standard to BS EN 206-1 — Part 1: Method of 
specifying and guidance for the specifier. 
 
BS 8500-2:2002, Concrete — Complementary British Standard to BS EN 206-1 — Part 2: Specification for constituent materials and concrete. 
 
BS EN 642:1995, Prestressed concrete pressure pipes, cylinder and non-cylinder, including joints, fittings and specific requirement for prestressing steel for pipes. 
 
BS EN 752-2:1997, Drain and sewer systems outside buildings — Part 2: Performance requirements.  
BS EN 752-3:1997, Drain and sewer systems outside buildings — Part 3: Planning. 
 BS EN 752-4:1998, Drain and sewer systems outside buildings — Part 4: Hydraulic design and 
environmental considerations. 
 BS EN 1295-1:1998, Structural design of buried pipelines under various conditions of loading — Part 
1: General requirements. 
 
BS EN 1610:1998, Construction and testing of drains and sewers.  
 
  
 
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