ISO/TR 10465-3:2007

TECHNICAL ISO/TR
REPORT 10465-3
Second edition
2007-09-01

Underground installation of flexible
glass-reinforced pipes based
on unsaturated polyester resin
(GRP-UP) —
Part 3:
Installation parameters and application
limits
Installation enterrée de canalisations flexibles renforcées de fibres
de verre à base de résine polyester insaturée (GRP-UP) —
Partie 3: Paramètres d'installation et limites d'application




Reference number
ISO/TR 10465-3:2007(E)
©
ISO 2007

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ISO/TR 10465-3:2007(E)
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ISO/TR 10465-3:2007(E)
Contents Page
Foreword. iv
Introduction . v
1 Scope .1
2 Normative references .1
3 Symbols and abbreviated terms .1
4 Parameters for deflection calculations when using an ATV-A 127 type design system.10
4.1 Initial deflection.10
4.2 Long-term deflection calculated using an ATV-A 127 type design system.16
5 Soil parameters, strain coefficients and shape factors for flexural strain calculations .17
5.1 For equations used in ATV-A 127 type design systems.17
5.2 Shape factor, D .19
f
6 Influence of soil moduli and pipe stiffness on pipe buckling calculations using ATV-A 127
type design systems .22
6.1 Elastic buckling under internal negative pressure for depths of cover over 1 m.22
6.2 Long-term buckling under sustained external load.23
6.3 Value for S .23
O
7 Parameters for rerounding and combined loading calculations .23
7.1 Rerounding.23
7.2 Combined effects of internal pressure and external bending loads.23
8 Traffic loads.24
8.1 General.24
8.2 Influence on allowable initial deflection.24
8.3 Soil pressure from traffic loads.24
9 Influence of sheeting.24
10 Safety factors for gravity pipes and pressure pipes.25
10.1 Gravity pipes .25
10.2 Pressure pipes .27
10.3 Safety factors in buckling calculations .29
Annex A (informative) Soil parameters .30
Annex B (informative) Determination of concentration factors used in ATV-A 127.42
Annex C (informative) Loading coefficients used in ATV-A 127 .43
Annex D (informative) Horizontal bedding correction factors.44
Annex E (informative) Selection of long-term stiffness .46
Annex F (informative) Partly residual soil friction used in ATV-A 127 type calculation systems.48
Annex G (informative) Application limits for GRP pressure pipes installed underground .50
Bibliography .63
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ISO/TR 10465-3:2007(E)
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.
International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.
The main task of technical committees is to prepare International Standards. Draft International Standards
adopted by the technical committees are circulated to the member bodies for voting. Publication as an
International Standard requires approval by at least 75 % of the member bodies casting a vote.
In exceptional circumstances, when a technical committee has collected data of a different kind from that
which is normally published as an International Standard (“state of the art”, for example), it may decide by a
simple majority vote of its participating members to publish a Technical Report. A Technical Report is entirely
informative in nature and does not have to be reviewed until the data it provides are considered to be no
longer valid or useful.
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.
ISO 10465-3 was prepared by Technical Committee ISO/TC 138, Plastics pipes, fittings and valves for the
transport of fluids, Subcommittee SC 6, Reinforced plastics pipes and fittings for all applications.
This second edition cancels and replaces the first edition (ISO 10465-3:1999), which has been technically
revised to take into account changes made to methods in base documents ATV-A 127 and AWWA M-45 (see
Introduction).
ISO 10465 consists of the following parts, under the general title Underground installation of flexible glass-
reinforced pipes based on unsaturated polyester resin (GRP-UP):
⎯ Part 1: Installation procedures [Technical Specification]
⎯ Part 2: Comparison of static calculation methods [Technical Report]
⎯ Part 3: Installation parameters and application limits [Technical Report]
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ISO/TR 10465-3:2007(E)
Introduction
Work in ISO/TC 5/SC 6 (now ISO/TC 138) on writing International Standards for the use of glass-reinforced
plastics (GRP) pipes and fittings was approved at the subcommittee meeting in Oslo in 1979. An ad hoc group
was established and the responsibility for drafting various International Standards was later given to a Task
Group (now ISO/TC 138/SC 6).
At the SC 6 meeting in London in 1980, Sweden proposed that a working group be formed to develop
documents regarding a code of practice for GRP pipes. This was approved by SC 6, and Working Group 4
(WG 4) was formed for this purpose. Since 1982, many WG 4 meetings have been held which have
considered the following matters:
⎯ procedures for the underground installation of GRP pipes;
⎯ pipe/soil interaction with pipes having different stiffness values;
⎯ minimum design parameters;
⎯ overview of various static calculation methods.
During the work of WG 4, it became evident that unanimous agreement could not be reached within the
working group on the specific methods to be employed to address these issues. It was therefore agreed that
all parts of the code of practice should be made into a type 3 Technical Report, and this was the form in which
this part of ISO 10465 was first published in 1999. Since then the ISO rules dealing with the classification of
document types have been revised and this has resulted in the three parts of ISO 10465 now being published
as either a Technical Specification or a Technical Report.
ISO 10465-1, published as Technical Report in 1993 and revised as a Technical Specification in 2007,
describes procedures for the underground installation of GRP pipes. It concerns particular stiffness classes for
which performance requirements have been specified in at least one product standard, but it can also be used
as a guide for the installation of pipes of other stiffness classes.
ISO 10465-2, published as a Technical Report in 1999 and revised in 2007, presents a comparison of the two
primary methods used internationally for static calculations on underground GRP pipe installations.
These methods are
a) the ATV method given in ATV-A 127, Guidelines for static calculations on drainage conduits and
pipelines, and
b) the AWWA method given in AWWA manual M-45, Fiberglass pipe design.
This part of ISO 10465, published as a Technical Report in 2007, gives additional information, which is useful
for static calculations primarily when using an ATV-A 127 type design system in accordance with
ISO 10465-2, on items such as:
parameters for deflection calculations;
soil parameters, strain coefficients and shape factors for flexural-strain calculations;
soil moduli and pipe stiffness for buckling calculations with regard to elastic behaviour;
parameters for rerounding and combined-loading calculations;
the influence of traffic loads;
the influence of sheeting;
safety factors.
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ISO/TR 10465-3:2007(E)
This Technical Report is not to be regarded as an International Standard. It is proposed for provisional
application so that experience may be gained on its use in practice. Comments should be sent to the
secretariat of TC 138/SC 6.
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TECHNICAL REPORT ISO/TR 10465-3:2007(E)

Underground installation of flexible glass-reinforced pipes
based on unsaturated polyester resin (GRP-UP) —
Part 3:
Installation parameters and application limits
1 Scope
This part of ISO 10465 gives supplementary information on parameters and application limits for the
underground installation of flexible glass-reinforced pipes based on unsaturated polyester resin (GRP-UP). It
is particularly relevant when using an ATV-A 127 type design system.
Explanations for the long-term safety factors incorporated into the GRP system standards based on simplified
probabilistic methods are provided in Annex G.
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.
ATV-A 127, Guidelines for static calculations on drainage conduits and pipelines, 3rd edition, August 2000,
(German Association for Water Pollution Control)
AWWA M-45, Fiberglass pipe design manual M-45, 2005 (American Water Works Association)
3 Symbols and abbreviated terms
For the purposes of this document, the following symbols apply.
NOTE 1 This clause also contains symbols and abbreviations from ISO 10465-1 and ISO 10465-3 for completeness.
NOTE 2 Several identical symbols are used in ATV-A 127 and AWWA M-45 to represent different quantities, and
where this occurs, the origin of the symbol is given in the rightmost column.
NOTE 3 The format of the symbols listed here has been aligned as far as practicable with the ISO/IEC Directives, part
2, namely they appear in Times New Roman italic font. This format may differ slightly from the format used in ATV-A 127
and AWWA M-45.
Symbol Unit Meaning
AQL — acceptable quality level
a′ — effective relative projection
a — ageing factor (ATV)
f
a — distribution factor (AWWA)
f
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ISO/TR 10465-3:2007(E)
B1, B2, B3, B4 — embedment conditions
b m trench width at spring-line
b′ m distance from trench wall to pipe (see Figure 1)
C — buckling scalar calibration factor
n
c , c , c , c — coefficients used to determine ζ
1 2 3 4
c — reduction factor
4
c — creep factor
f
cc,,c ,,c c ,,c — deformation coefficients
h,qv v,qh v,qh* h,qh h,qh* v,qv
c,,,ccc
v* v,qh* h,qh* v*
D mm mean pipe diameter
D — shape factor
f
D — shape adjustment factor
g
D — deflection lag factor
L
D % compaction (based on simple proctor)
pr
d m external pipe diameter
e
d m internal pipe diameter
i
d m mean pipe diameter ⎡de×1000 − ⎤
( )
m e
⎣ ⎦
d mm vertical deflection
v
d mm maximum permissible long-term deflection
vA
d mm vertical deflection at rupture
vR
dd % maximum permissible relative vertical deflection
()
vm
permissible
(dd ) % initial vertical deflection
vm
initial
dd % long-term (50 year) vertical deflection
( )
vm
50
(dd ) % ultimate long-term vertical deflection
vm
ult
2
EE,,E,E N/m apparent flexural moduli of pipe wall
o p t,wet
2
E′′,,EE,E,E,E,E,E ,E N/m soil deformation moduli
12 3 4 s s s,σ 20
2
E N/m tensile hoop modulus
TH
e mm pipe wall thickness
e — base of natural logarithms (2,718 281 8)
F — compaction factor
F , F kN wheel loads
A E
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ISO/TR 10465-3:2007(E)
FS — calculated safety factor (ATV)
FS — design factor = 2,5 (AWWA)
FS — bending safety factor
b
FS — pressure safety factor
pr
f — reduction factor for creep
1
f — reduction factor for ground water in pipe zone
2
G1, G2, G3, G4 — soil groups
HDB — extrapolated pressure strain at 50 years
H m environmental depth of cover
EVD
h m depth of cover to top of pipe
h m depth at which load from wheels interact
int
h m height of water surface above top of pipe
w
4
I m /m second moment of area in longitudinal direction per unit
length (of a pipe)
I — impact factor (AWWA)
f
2
i N/mm installation factor
f
*
K — coefficient for bedding reaction pressure
K′ — modulus of deformation
K , K — ratio of horizontal to vertical soil pressure in soil zones
1 2
1 and 2
K — ratio of horizontal to vertical soil pressures in pipe-zone
3
backfill, when backfill is at top of pipe (see
ISO 10465-3:2007, Annex A)
k — reduction factor to take into account the elastic-plastic
v2
soil mass law and preliminary deflections
k — bedding coefficient
x
L m load width parallel to direction of travel
1
L m load width perpendicular to direction of travel
2
LLDF — live load as a function of depth factor
M — sum of bending moments
M — multiple presence factor
p
2
M N/m composite constrained-soil modulus
s
2
M N/m value of composite constrained-soil modulus from
s1
ISO 10465-3:2007, Table A.3
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ISO/TR 10465-3:2007(E)
2
M N/m composite constrained-soil modulus at 100 % SPD
s100
2
M N/m backfill soil constrained modulus
sb
2
M N/mm native soil constrained modulus
sn
mm,,m
— moment factors
qv qh qh*
N — sum of normal forces
n — number of blows
10
P N magnitude of wheel load
PN — nominal pressure (pipe characteristic)
P bar internal pressure
P — probability of failure
f
2
P MPa (N/mm) internal under-pressure
v
2
P N/m working pressure
w
P(X) — probability function
P bar long-term (50 year) failure pressure
50
2
p N/m soil stress resulting from traffic loads
2
p N/mm pressure due to prismatic soil load
E
2
p N/mm external water pressure
e
2
p N/m soil stress due to traffic load according to Boussinesq
F
2
p N/m soil pressure due to uniformly distributed surface load
o
2
p N/mm soil pressure resulting from traffic load
v
2
q MPa (N/mm) permissible buckling pressure
a
2
q MPa (N/mm) critical buckling pressure
c
2
q MPa (N/mm ) critical buckling pressure under sustained load
cl
2
q N/mm horizontal bedding reaction for pipe and contents
c*w
2
q , q N/mm horizontal or vertical soil pressure on pipe
h v
2
q N/mm horizontal bedding reaction pressure
h*
2
q N/mm reduced long-term horizontal soil pressure
hLT
2
q N/mm long-term (50 year) horizontal soil pressure
h,50
2
q N/mm reduced long-term vertical soil pressure
vLT
2
q N/mm long-term (50 year) vertical soil pressure
v,50
2
q N/mm vertical load due to pipe and contents
vwa
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ISO/TR 10465-3:2007(E)
R — depth-of-fill correction factor
h
R — water buoyancy reduction factor
w
r — rerounding factor (AWWA)
r m mean pipe radius (AWWA)
r , r m wheel radii (ATV)
A E
r — rerounding coefficient
c
r m pipe internal radius
i
r m mean pipe radius
m
2
S N/mm horizontal bedding stiffness
Bh
2
S N/mm vertical bedding stiffness
Bv
S — long-term ring-bending strain capability of the pipe
b
S — soil support combining factor
c
2
S N/mm characteristic stress
k
2
S N/m long-term pipe stiffness
O
2
S N/m long-term pipe stiffness
O,50
2
S N/m weighted long-term pipe stiffness
o
2
S N/m long-term (50 year) pipe stiffness
OK
2
S N/m long-term (2 year) pipe stiffness
OL
SPD % standard proctor density
2
S N/m initial pipe stiffness
p
2
S N/m long-term pipe stiffness
p,50
−6
2
S ××810
S N/mm
p
R
−6
2
S N/mm S ××810
R,50 p,50
2
S N/mm standard deviation of strength of pipe
Res
2
S N/mm standard deviation of strength of pipe below ground
Res,B
2
S N/mm standard deviation of stress in pipe
S
2
S N/mm standard deviation of stress in pipe below ground
S, B
t m length of tyre footprint
l

t m width of tyre footprint
w
V — system stiffness
RB
V — stiffness ratio
S
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ISO/TR 10465-3:2007(E)
2
W N/m vertical soil load on pipe
c
2
W N/m traffic load
L
X — safety index
y % coefficient of variation for initial tensile strength
y % coefficient of variation for tensile strength
R
z % coefficient of variation for initial ultimate deflection
α ° half the bedding angle (see Figure 2)
α — reduction factor depending upon trench proportions and
B
embedding conditions
α — value from ISO 10465-2:2007, Figure 5
Bi
α — snap-through coefficient
D
ακ, ακ , ακ — correction factor for extreme curvature of inner or outer
i e
edge
β ° half the horizontal support angle (see Figure 2)
β ° (ATV) trench wall slope angle (see Figure 1)
3
γ N/m bulk density of backfill material
b
3
γ N/m density of pipe contents
w
δ ° trench wall friction angle
δ % relative horizontal deflection
h
δ % relative vertical deflection
v
δ % negative relative vertical deflection due to traffic and
va
vacuum load
δ , δ % negative relative vertical deflection due to soil load
vc vs
δ % long-term relative vertical deflection
v50
δ % positive relative vertical deflection due to backfilling in
vio
pipe zone
δ % negative relative vertical deflection due to installation
viv
irregularities
δ % long-term negative relative vertical deflection due to soil
vs50
load
δ % negative relative vertical deflection due to weight of
vw
pipe
δ % relative vertical deflection due to traffic load
w
ε — bending strain caused by maximum permitted deflection
b
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ISO/TR 10465-3:2007(E)
ε — compressive strain due to vertical load
comp
ε, ε , ε — calculated flexural strains in pipe wall
t f
ε — flexural strain due to installation irregularities
if
ε , ε — maximum permissible strain due to pressure
max R
ε — initial bending tensile strain
PK
ε — long-term bending tensile strain
PL
ε — calculated strain in pipe wall due to internal pressure
pr
ε — weighted calculated value of outer fibre strain
R
ε — total flexural strain
tot
ε — flexural strain due to total vertical load
v
ε — flexural strain due to backfilling in pipe zone
vio
ε — flexural strain due to weight of pipe
vw
ε — flexural strain due to pipe contents
w
ε — long-term maximum bending strain caused by
50
maximum permitted deflection
ζ — correction factor for horizontal bedding
η,,ηη,η — safety factors
tf ff
η — combined flexural safety factor
haf
η — combined tensile safety factor
hat
η — redefined safety factor for pipe to operate at PN
t,PN
ϕ ° soil internal friction angle
ϕ′ — impact factor (ATV)
ϕ — variability factor for compacted soil
s
χ — coefficient of safety
3
χ MN/m unit weight (density) of pipe material
P
3
χ N/m unit weight (density) of soil
s
3
χ N/m unit weight (density) of water
w
κκ,
— reduction factor for distributed load according to silo
β
theory when trench angle, β, is 90°
κκ, — reduction factor for distributed load according to silo
ooβ
theory when trench angle, β, is not 90°
λ , λ , λ , λ , λ , λ — concentration factors in soil next to pipe
B B50 P PG PG50 S
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ISO/TR 10465-3:2007(E)
λ — maximum concentration factor
max
λ — long-term value for λ
PLT P
λ — reduction factor for soil friction with time
R
2
µ N/mm mean value of pipe strength (resistance)
Res
2
µ N/mm mean value of strength (resistance) of pipe above
Res, A
ground
2
µ N/mm mean value of strength (resistance) of pipe below
Res, B
ground
2
µ N/mm mean value of stress in pipe below ground
S,B
v — Poisson ratio of soil
s
3
ρ MN/m density of pipe wall material
2
σ N/mm calculated compressive stress in pipe wall
c
σ — initial bending tensile stress
PK
σ — long-term bending tensile stress
PL
σ — weighted bending tensile stress
R
2
σ N/mm calculated tensile stress in pipe wall
t

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ISO/TR 10465-3:2007(E)

Key
1 ground level 7 trench wall angle, β
2 water table 8 thickness of primary embedment
3 height of water surface above top of pipe, h 9 thickness of bedding
w
4 vertical deflection, d 10 thickness of foundation (if required)
v
5 distance from trench wall to pipe, b′ 11 pipe embedment
6 depth of cover to top of pipe, h 12 thickness of backfill
Soil moduli zones
E1 trench backfill above pipe embedment
E2 pipe embedment
E3 undisturbed native soil or in situ material to side of trench
E4 undisturbed native soil or in situ material below bottom of trench (foundation material)
NOTE 1 The AWWA M-45 design manual uses M in zone E .
sb 2
NOTE 2 The AWWA M-45 design manual uses M in zones E and E .
sn 3 4
Figure 1 — Symbols and terminology
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ISO/TR 10465-3:2007(E)
4 Parameters for deflection calculations when using an ATV-A 127 type design
system
This clause covers the recommended soil parameters and deflection coefficients to use when calculating the
initial or long-term deflections in accordance with ATV-A 127.
NOTE In the following calculations deflections having a negative value indicate a reduction in vertical diameter.
4.1 Initial deflection
The measurement of the initial deflection shortly after installation, when the effects of traffic loads are not
present, is a very easy way to assess and control the quality of the installation. A calculation of initial
deflection should be done for this loading condition.
ATV-A 127 and the AWWA M-45 design manual do not address effects of installation variability, deflection
resulting from the pipe's own weight, and the reduction in deflection from the upwards ovalization of the pipe
when the pipe zone backfill is compacted. It is recommended that, for deflection calculations, these effects be
considered in addition to the effects of soil and superimposed loads. This recommendation is made because
these matters have been found significant in practice, especially for pipes having a DN greater than 2000.

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ISO/TR 10465-3:2007(E)

a)  Spangler

b)  ATV
Figure 2 — Soil stress distribution according to Spangler and ATV-A 127
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ISO/TR 10465-3:2007(E)
4.1.1 Deflection from vertical soil load and superimposed loads but excluding traffic loads
The change in vertical diameter, δ , as a result of external loads is determined using Equation (1).
v
NOTE 1 This deflection has a negative value which indicates a reduction in vertical diameter.
2 × r
m
⎡⎤
δ=×Cq+Cq×+C×q (1)
()( )( )
v v,qv v v,qh h v,qh* h*
⎣⎦
8
This can be converted into relative vertical deflection, in %, δ , using
vs
∆d
v
δ=×100
vs

2 × r
m
The horizontal change in diameter is determined, if necessary, using Equation (2):
2 × r
m
⎡⎤
δ=×Cq+Cq×+C×q (2)
()( )( )
h h,qv v h,qh h h,qh* h*
⎣⎦
8
where
δ is the negative relative vertical deflection from soil load;
vs
r is the mean radius of the pipe wall;
m
C is the deformation coefficient for δ as a result of q ;
v,qv v v
C is the deformation coefficient for δ as a result of q ;
v,qh* h h
cc,,cc, are deformation coefficients (see Tables 1 and 2 and Annex C);
v,qv v,qh* h,qv h,qh*
⎡⎤
qh=×λκχ×+κ×p (3)
()( )
vPG S o o
⎣⎦
⎡⎤⎛⎞d
e
qK=×λκ×χ×h+κ×p + χ× (4)
()
⎢⎥⎜⎟
h2 S S o o S
2
⎝⎠
⎣⎦
Cq×+C ×q
( ) ( )
h,qv v h,qh h
q = (5)
h*
VC−
RB h,qh
where
2
q is the vertical soil pressure on pipe, in N/mm ;
v
2
q is the horizontal soil pressure on pipe, in N/mm ;
h
2
q is the horizontal bedding reaction pressure, in N/mm ;
h*
λ is the concentration factor for trench widths less than 4 d ;
PG e
⎛⎞
λ−−14b λ
PP
λ = ⎜⎟×+ (6)
PG
⎜⎟
33d
⎝⎠e
NOTE Based on experience, the limits given for λ for GRP pipes in ATV-A 127 are not normally reached.
PG
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ISO/TR 10465-3:2007(E)
b is the trench width, in metres;
d is the external diameter of pipe, in metres;
e
λ is the concentration factor for the soil above the pipe (see Annex B);
P
κ is the silo theory reduction factor for friction (see ISO/TR 10465-2 and Annex F);
3
χ is the bulk density of the soil (i.e. its weight per unit volume), in N/m ;
S
h is the depth of cover to top of pipe, in m;
κ is the silo theory reduction factor for a uniformly distributed load (UDL), (see ISO 10465-2 and
o
Annex F);
2
p is the soil pressure applied by a UDL, in N/mm ;
o
K is the ratio of the horizontal to the vertical pressure at the pipe spr
...