BS ISO 16134:2020 pdf download – Earthquake-resistant and subsidence- resistant design of ductile iron pipelines
This document specifies the design of earthquake-resistant and subsidence-resistant ductile ironpipelines suitable for use in areas where seismic activity and land subsidence can be expected. Itprovides a means of determining and checking the resistance of buried pipelines and gives examplecalculations. It is applicable to ductile iron pipes and fittings with joints as specified in lso 2531,ISO 7186 and lSo 16631 that have expansion/contraction and deflection capabilities, used in pipelinesburied underground.
NOTE Subsidence is not the effects of an earthquake or a sinkhole.
The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document. For dated references, only the edition cited applies.Forundated references, the latest edition of the referenced document(including any amendments) applies.
ISO 2531, Ductile iron pipes, fittings, accessories and their joints for water applications
3 Terms and definitions
For the purposes of this document, the terms and definitions given in lSo 2531and the following apply.ISO and IEC maintain terminological databases for use in standardization at the following addresses:- ISO online browsing platform: available at https://www.iso.org/obp
一IEC Electropedia: available at http://www.electropedia.org/
placing of pipes underground in a condition where they touch the soil directly3.2
response displacement method
earthquake-resistant calculation method in which the underground pipeline structure is affected bythe ground displacement in its axial direction during an earthquake
phenomenon in which sandy ground rapidly loses its strength and rigidity due to repeated stress duringan earthquake, and where the whole ground behaves just like a liquid
joint having slip out resistance as well as expansion/contraction and deflection capabilities3.5
joint having expansion and deflection capabilities
4 Earthquake-resistant design
4.1 Seismic hazards to buried pipelines
In general, there are several main causes of seismic hazards to buried pipelines:
a) ground displacement and ground strain caused by seismic ground shaking;
b) ground deformation such as a ground surface crack, ground subsidence and lateral spread induced by liquefaction;
c) relative displacement at the connecting part with the structure, etc.;
d) ground displacement and rupture along a fault zone.
Since the ductile iron pipe has high tensile strength as well as the capacity for expansion/contraction and deflection from its joint part, giving it the ability to follow the ground movement during the earthquake, the stress generated on the pipe body is relatively small. Few ruptures of pipe body have occurred during earthquakes in the past. It is therefore important to consider whether the pipeline can follow the ground displacement and ground strain without slipping out of joint when considering its earthquake resistance. The internal hydrodynamic surge pressures induced by seismic shaking are normally small enough not to be considered.
4.2 Qualitative design considerations
To increase the resistance of ductile iron pipelines to seismic hazards, the following qualitative design easures should be taken into consideration.
a) Provide pipelines with expansion/contraction and deflection capability.
EXAMPLE Use of shorter pipe segments, special joints or sleeves and anti-slip-out mechanisms according to the anticipated intensity or nature of the earthquake.
b) Lay pipelines in a firm foundation.
c) Use smooth back fill materials.
NOTE Polyethylene sleeves and special coating are also effective in special cases.
d) Install more valves.
4.2.2 Where high earthquake resistance is needed
It is desirable to enhance the earthquake resistance of parts connecting the pipelines to structures and when burying the pipes in
a) soft ground such as alluvium,
b) reclaimed ground,
c) filled ground,
d) suddenly changing soil types (geology) or topography,
e) sloping ground,
f) near revetments,
g) liquefiable ground, and/or
h) near an active fault.
4.3 Design procedure
To make earthquake-resistant design for ductile iron pipelines:
a) select the piping route;
b) investigate the potential for earthquakes and ground movement;
c) assume probable earthquake motion (seismic intensity);
d) undertake earthquake resistance calculation and safety checking;
e) select joints.
Solid/firm foundations should be chosen for the pipeline route.BS ISO 16134 pdf download.