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The French Association for Earthquake Engineering (AFPS in French) edited last year new guidelines dedicated to evaluate seismic risks for steel buried transmission pipelines. This work has been done in cooperation with the gas operators and the French Regulator as earthquake regulations have been recently evolving.
Today, another group has been constituted and is aimed at making guidelines dedicated to distribution pipelines and especially polyethylene pipes which are made of a visco-elasto- plastic material quite different from elasto-plastic steel. This group entails seismic experts, PE experts and the French distribution operators who own more than 150,000 km of PE pipes.
This paper presents the first part of the guidelines which are: an exhaustive feedback for distribution pipelines; the seismic loading relevant to distribution pipelines in the French context and the test program which is intended to be performed at CRIGEN, the Centre of Research and Innovation for Gas and New Energies during the work.
The test program consists on the one hand in performing dynamic loading of PE pipes under pressure to simulate the vibratory part of the earthquake. On the other hand, pipes are submitted to displacements to simulate faults or liquefaction-induced movements.
Both series of tests are completed with non-destructive evaluation by mean of the Phased Array Ultrasonic Technique on the pipes before and after the loadings.
Both series of pipes are then submitted to hydraulic pressure at 80°C in order to evaluate their residual mechanical performances according to the standards. The tested PE pipes come both from CRIGEN’ stock (properly stored and not operated) and from the field with a 35-year operation life pipe.
Results and discussion will be presented in the paper.