Abstract
Pipelines are linear structures that cross various slope geometries and geologies and are susceptible to various ground movement geohazards, including landslides and subsidence. The ground movements from the geohazards can potentially induce axial, bending, and torsional stresses in pipelines.
The objective of this paper is to summarize the strain relief process, demonstrate that strains can be estimated without IMU using the shape of the pipe measured in the field, and describe the pipeline performance before, during and after stress-relief excavation.
This paper will also present planning considerations prior to conducting a stress-relief excavation, including design considerations, geotechnical stability, and considerations related to conditions of the pipe. This paper will present an approach to approximate pipe shape and estimate bending strains in the pipe and includes a discussion on results of three case-studies of stress-relief excavations. These case studies include landslide movements of various directions with respect to a pipeline. A summary of pipeline out-of-straightness, inertial measurement unit bending strain, rebound measurement during the stress-relief excavation, and strain measurement using strain gauges are included.
