ISO 16611:2017

INTERNATIONAL ISO
STANDARD 16611
First edition
2017-06
Plastics piping systems for drainage
and sewerage without pressure —
Non-circular pipes and joints made
of glass-reinforced thermosetting
plastics (GRP) based on unsaturated
polyester resins (UP) — Dimensions,
requirements and tests
Systèmes de canalisation en plastiques pour réseaux d’assainissement
sans pression — Tuyaux non-circulaires, assemblages de tuyaux et
raccords en plastiques thermodurcissables renforcés de verre (PRV) à
base de résines de polyester non saturé (UP) — Dimensions, exigences
et essais
Reference number
©
ISO 2017
© ISO 2017, Published in Switzerland
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ii © ISO 2017 – All rights reserved

Contents Page
Foreword .v
Introduction .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 2
4 General requirements . 8
4.1 Classification . 8
4.1.1 Categories . 8
4.1.2 Nominal size . 8
4.2 Materials . 8
4.2.1 General. 8
4.2.2 Reinforcement . 8
4.2.3 Resin . 8
4.2.4 Aggregates and fillers . 9
4.2.5 Elastomers . 9
4.2.6 Metals . 9
4.3 Wall construction . 9
4.3.1 Inner layer . 9
4.3.2 Structural layer . 9
4.3.3 Outer layer . 9
4.3.4 Appearance . 9
4.4 Reference conditions for testing .10
4.4.1 Temperature .10
4.4.2 Properties of water for testing .10
4.4.3 Loading conditions . .10
4.4.4 Conditioning .10
4.4.5 Measurement of dimensions .10
4.4.6 Elapsed time for determination of long-term properties, (x) .10
4.5 Joints .10
4.5.1 General.10
4.5.2 Types of joint .10
4.5.3 Flexibility of the jointing system .10
4.5.4 Sealing ring .11
4.5.5 Adhesives . .11
5 Pipes .11
5.1 Geometrical characteristics .11
5.1.1 Dimensions .11
5.2 Mechanical characteristics.12
5.2.1 General.12
5.2.2 Short-term bending modulus .13
5.2.3 Long-term creep bending modulus .14
5.2.4 Short-term bending strength .14
5.2.5 Long-term bending strength .15
5.2.6 Resistance to strain corrosion .16
5.2.7 Minimum initial longitudinal tensile strength .17
5.3 Marking .18
6 Fittings .19
6.1 All types .19
6.1.1 General.19
6.1.2 Diameter series .19
6.1.3 Mechanical characteristics of fittings .19
6.1.4 Installed leak tightness of fittings .19
6.1.5 Dimensions .19
6.2 Marking .19
7 Joint performance .20
7.1 General .20
7.1.1 Requirements .20
7.1.2 Test temperature .20
7.1.3 Dimensions .20
7.2 Flexible joints .20
7.2.1 General.20
7.2.2 Maximum allowable draw .20
7.2.3 Maximum allowable angular deflection .20
7.2.4 Maximum allowable misalignment .20
7.2.5 Flexible non-end-load-bearing joints with elastomeric sealing rings .20
7.3 Rigid joints .22
7.3.1 Wrapped or cemented . .22
Annex A (informative) Examples for static calculation .24
Bibliography .25
iv © ISO 2017 – All rights reserved

Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity assessment,
as well as information about ISO’s adherence to the World Trade Organization (WTO) principles in the
Technical Barriers to Trade (TBT) see the following URL: www . i so .org/ iso/ foreword .html.
The committee responsible for this document is ISO/TC 138, Plastics pipes, fittings and valves for the
transport of fluids, Subcommittee SC 6, Reinforced plastics pipes and fittings for all applications.
Introduction
The goal to establish this product standard is to standardize the requirements for non-circular GRP pipes.
This document specifies the requirements for non-circular GRP pipe systems, designed to be used for
the renovation of existing channels or open cut installation.
This document specifies dimensions, requirements and tests of non-circular pipes including short and
long-term properties. To establish long-term properties, it is recommended to use the circular pipes
samples.
Annex A shows commonly used calculation methods but only as information. The calculation method is
selected by the designer.
This document does not include the recommended practice for installation as this should be a separate
document.
vi © ISO 2017 – All rights reserved

INTERNATIONAL STANDARD ISO 16611:2017(E)
Plastics piping systems for drainage and sewerage
without pressure — Non-circular pipes and joints made
of glass-reinforced thermosetting plastics (GRP) based
on unsaturated polyester resins (UP) — Dimensions,
requirements and tests
1 Scope
This document specifies the required properties of the piping system and its components made from
glass-reinforced thermosetting plastics (GRP) based on unsaturated polyester resin (UP) intended to
be used for drainage or sewerage without pressure including culverts.
It is the responsibility of the purchaser or specifier to make the appropriate selections taking into
account their particular requirements and any relevant national regulations and installation practices
or codes.
This document is applicable to non-circular GRP-UP pipes, with flexible or rigid joints, primarily
intended for use in buried installations but may also be used to reline existing non-circular pipe lines.
NOTE 1 GRP-UP includes pipes with vinyl ester liners or made entirely from vinyl ester.
NOTE 2 Piping systems conforming to this document can be used also for non-buried applications provided
the influence of the environment, e.g. from UV-radiation, and the supports are considered in the design of the
pipes, fittings and joints.
This document is applicable to pipes, fittings and their joints of nominal sizes from DN 150 to DN 4000,
which are intended to be used for the conveyance of surface water or sewage at temperatures up to 50 °C.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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.
ISO 75-2:2013, Plastics — Determination of temperature of deflection under load — Part 2: Plastics
and ebonite
ISO 178, Plastics — Determination of flexural properties
ISO 3126, Plastics piping systems — Plastics components — Determination of dimensions
ISO 4633, Rubber seals — Joint rings for water supply, drainage and sewerage pipelines — Specification for
materials
ISO 8513:2016, Plastics piping systems — Glass-reinforced thermosetting plastics (GRP) pipes — Test
methods for the determination of the initial longitudinal tensile strength
ISO 8533, Plastics piping systems for pressure and non-pressure drainage and sewerage — Glass-reinforced
thermosetting plastics (GRP) systems based on unsaturated polyester (UP) resin — Test methods to prove
the design of cemented or wrapped joints
ISO 8639, Glass-reinforced thermosetting plastics (GRP) pipes and fittings — Test methods for leaktightness
and proof of structural design of flexible joints
ISO 10468, Glass-reinforced thermosetting plastics (GRP) pipes — Determination of the long-term specific
ring creep stiffness under wet conditions and calculation of the wet creep factor
ISO 10928, Plastics piping systems — Glass-reinforced thermosetting plastics (GRP) pipes and fittings —
Methods for regression analysis and their use
ISO 10952, Plastics piping systems — Glass-reinforced thermosetting plastics (GRP) pipes and fittings —
Determination of the resistance to chemical attack for the inside of a section in a deflected condition
EN 681-1, Elastomeric seals — Material requirements for pipe joint seals used in water and drainage
applications — Part 1: Vulcanized rubber
EN/TS 14632, Plastics piping systems for drainage, sewerage and water supply, pressure and non-pressure
— Glass-reinforced thermosetting plastics (GRP) based on unsaturated polyester resin (UP) — Guidance for
the assessment of conformity
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http:// www .electropedia .org/
— ISO Online browsing platform: available at http:// www .iso .org/ obp
3.1
nominal size
BN × HN
alphanumerical designation of size, which is common to all components in a piping system, it is a
convenient pair of numbers for reference purposes that is related to the maximum internal breadth (B)
and the maximum internal height (H)
Note 1 to entry: The designation for reference or marking purposes consists of the letters BN(B) × HN(H) and the
numerical values for (B) and (H), when expressed in millimetres.
3.2
declared dimensions
dimensions which a manufacturer states to be the internal breadth (B) and height (H) produced in
respect of a particular nominal size BN × HN
3.3
specific ring stiffness
S
physical characteristic of a circular pipe which is a measure of the resistance to ring deflection per
metre length under external load
Note 1 to entry: Specific ring stiffness is determined using formula below and is expressed in Newtons per square
metre (N/m ):
EI⋅
S =
d
m
where
E is the apparent modulus of elasticity, which can be derived from the result of the ring stiffness
test, i.e. ISO 7685, expressed in Newtons per square metre (N/m );
d is the mean diameter of the pipe, in metres (m) (see 3.5);
m
2 © ISO 2017 – All rights reserved

I is the second moment of area in the longitudinal direction per metre length, in metres to the
fourth power per metre, (m /m):
e
I=
where
e is the wall thickness, in metres.
3.4
initial specific ring stiffness
S
value of S obtained when a circular pipe is tested in accordance with ISO 7685
Note 1 to entry: Initial specific ring stiffness is expressed in newtons per square metre (N/m ).
3.5
mean diameter
d
m
diameter of the circle corresponding with the middle of a circular pipe wall cross section
Note 1 to entry: Mean diameter is derived using the formula with the inside diameter and wall thickness
expressed in metres (m):
dI=+De
m
where
e is the pipe’s wall thickness.
3.6
wet creep factor
α
x,creep,wet
ratio of the long-term specific ring stiffness, S to the initial specific ring stiffness, S at x years
x,wet 0
Note 1 to entry: See 4.4.6 for value of x.
Note 2 to entry: Determined using circular test-pieces under sustained diametrical loading in wet conditions
when tested in accordance with ISO 10468
.
Note 3 to entry: Wet creep factor is a dimensionless number given by the formula:
S
x,wet
α =
x,creep,wet
S
3.7
long-term specific ring stiffness
S
x,wet
determined value of specific ring stiffness S at x years for circular pipe
3.8
rerating factor
R
RF
multiplication factor that quantifies the relationship of a product’s mechanical, physical and chemical
properties under service conditions above 35 °C [design service temperature (3.16)] to those applicable
at a standard test temperature of 23 °C
3.9
short term bending strength
σ
f
maximum flexural stress sustained by the test specimen during a bending test, when tested in
accordance with ISO 178
Note 1 to entry: Short-term bending strength is determined using the following formula and is expressed in
megapascals (MPa):
3FL
σ =
f
2bh
where
σ is the flexural stress, in megapascals (MPa);
f
F is the load in newtons (N);
L is the span, in millimetres (mm);
h is the thickness of the specimen, in millimetres (mm);
b is the width of the specimen, in millimetres (mm).
3.10
long-term bending strength
σ
fx
calculated value of σ at x years for circular pipe
f
Note 1 to entry: Long-term bending strength is determined using methodology given in 5.2.5.3, using linear
regression analysis according to ISO 10928 on data of bending stress in hoop direction, and is expressed in
megapascals (MPa):
d
m
6⋅⋅fmax ⋅
2 π
σ = ⋅α
circ ki
le⋅
with
35⋅⋅de+
i
α =
ki
33⋅⋅de+
i
where
σ is the ring bendning stress, in megapascals (MPa);
circ
F is the maximum force, in newtons (N);
max
d is the mean diameter, in millimetres (mm);
m
d is the inside diameter, in (mm);
i
e is the structural wall thickness, in (mm);
l is the length of specimen, in (mm);
α is the correction factor inner surface.
ki
4 © ISO 2017 – All rights reserved

3.11
short term bending modulus
E
f
value of flexural modulus obtained when tested in accordance with ISO 178
Note 1 to entry: Short term bending modulus is determined using the following formula and is expressed in
megapascals (MPa):
F
L
max
E = ⋅
f
s
4bh⋅
max
where
E is bending modulus, in megapascals (MPa);
f
F is the maximum force corresponds to maximum deflection, in newtons (N);
max
s is the maximum deflection of specimen , in millimetres (mm);
max
b is the width specimen width, in (mm);
h is the wall thickness of the specimen, in (mm);
L is the span, in (mm).
3.12
long-term creep bending modulus
E
fx
calculated value of E at x years for circular pipe when tested in accordance with ISO 10468
f
Note 1 to entry: Long-term bending modulus is determined using the following formula and is expressed in
megapascals (MPa):
EE=⋅ α
f0xx ,creep,wet
where
E is the long-term creep bending modulus, in megapascals (MPa);
fx
E is the short-term bending modulus as result of the creep test on circular profiles according to
ISO 10468, in megapascals (MPa);
α is the wet creep factor, see 3.6.
x,creep,wet
3.13
type tests
tests carried out to prove that a material, component, joint or assembly is capable of conforming to the
relevant requirement
3.14
laying length
total length of a pipe minus, where applicable, the manufacturer’s recommended insertion depth of the
spigot(s) in the socket
Note 1 to entry: Laying length is expressed in metres (m).
3.15
normal service conditions
conveyance of surface water or sewage, in the temperature range 2 °C to 50 °C, with maximum water
table of 10 m, for 50 years
3.16
design service temperature
maximum sustained temperature at which the system is expected to operate
Note 1 to entry: Expressed in degrees Celsius (°C).
3.17
flexible joint
joint which allows relative movement between the pipes being joined
Note 1 to entry: Examples of this type of joint are: socket-and-spigot joint with an elastomeric sealing element
(including double socket designs)
3.18
rigid joint
joint which does not allow relative movement between the pipes being joined
Note 1 to entry: Examples of this type of joint are: flanged joint, including integral and loose flanges, wrapped or
cemented joint.
3.19
angular deflection
δ
angle between the axes of two adjacent pipes
Note 1 to entry: See Figure 1.
Note 2 to entry: Angular deflection is expressed in degrees (°).
3.20
draw
D
longitudinal movement of a joint
Note 1 to entry: See Figure 1.
Note 2 to entry: Draw is expressed in millimetres (mm).
3.21
total draw
T
sum of the draw, D, and the additional longitudinal movement, J, due to the presence of angular
deflection
Note 1 to entry: See Figure 1.
Note 2 to entry: Total draw is expressed in millimetres (mm).
3.22
misalignment
M
amount by which the centrelines of adjacent pipes fail to coincide
Note 1 to entry: See Figure 1.
Note 2 to entry: Misalignment is expressed in millimetres (mm).
6 © ISO 2017 – All rights reserved

a)
b)
c)
d)
Key
D draw
J longitudinal movement arising from angular deflection of the joint
δ angular deflection of the joint
T total draw
M misalignment
Figure 1 — Joint movement
4 General requirements
4.1 Classification
4.1.1 Categories
Pipes conforming to this document shall be classified according to nominal size (BN × HN) (see 3.1), and
joint type i.e. flexible or rigid (see 3.17 or 3.18).
4.1.2 Nominal size
The nominal size (BN × HN) (see 3.1) of pipes shall conform to the product declaration of the
manufacturer.
4.2 Materials
4.2.1 General
The pipe shall be constructed using chopped and/or continuous glass filaments, strands or rovings,
mats or fabric synthetic veils, and polyester resin with or without fillers and if applicable additives
necessary to impart specific properties to the resin. The pipe or fitting may also incorporate aggregates,
and if required a thermoplastic liner.
4.2.2 Reinforcement
The glass used for the manufacture of the reinforcement shall be one of the following types:
a) type “E” glass, comprising primarily either oxides of silicon, aluminium and calcium (alumino–
calcosilicate glass) or silicon, aluminium and boron (alumino-borosilicate glass);
b) type “C” glass, comprising primarily oxides of silicon, sodium, potassium, calcium and boron (alkali
metal calcium glass with an increased boron trioxide content) which is intended for applications
requiring enhanced chemical resistance;
c) type “R” glass, comprising primarily oxides of silicon, aluminium, calcium and magnesium without
added boron;
d) type “E-CR” glass, comprising boron-free modified E-glass compositions for improved resistance
to corrosion by most acids.
In any of these types of glass small amounts of oxides of other metals will be present.
NOTE These descriptions for “C” glass and “E” glass are consistent with, but more specific than those given
in ISO 2078.
The reinforcement shall be made from continuously drawn filaments of a glass conforming to type E,
type C or type R, and shall have a surface treatment compatible with the resin to be used. It may be
used in any form, e.g. as continuous or chopped filaments, strands or rovings, mat or fabric.
4.2.3 Resin
The resin used in the structural layer (see 4.3.2) shall have a temperature of deflection of at least
70 °C when tested in accordance with ISO 75-2:2013, meth
...