Empirical expressions for the maximum induced strain on buried steel pipelines crossing strike-slip faults

Abstract

Abstract Empirical expressions for estimating the maximum induced strain on buried steel pipelines crossing strike-slip faults are proposed. These expressions have been obtained through parametric studies involving finite element analyses of 18 different case loads of buried pipelines. The pipe and its soil surrounding were modeled in Abaqus software with shell and solid elements, respectively. Pipelines with different values of diameter, thickness, yielding strain and ultimate stress were analyzed under different values of fault displacement and pipe-fault crossing angle. The obtained response databank was used to develop empirical relations providing the maximum pipe strain in terms of geometrical, material and faulting characteristics of the problem. These expressions describe both the tensile and compressive modes of deformation and can be used in practice for the estimation of the maximum induced strain during the seismic design and/or evaluation of pipelines. It was found that the pipe type, bending angle and fault offset have pronounced effects on the behavior of the fault-crossing pipeline. On the other hand, the response of the pipeline was shown to be insensitive to the crossing angle due to the large strain caused by the section deformation, which occurs at any crossing angle.