Stress Test and Analysis of Pipeline Systems under Foundation Settlement in a Natural Gas Station

Abstract

The complex geological environment inside a natural gas station results in varying degrees of foundation settlement, which causes the deformation of pipelines and equipment and then results in natural gas leakage. A stress test platform of pipeline and equipment in a natural gas station was set up, and a strain test system was used to carry out the stress test of pipelines and equipment given different settlement conditions. Based on the platform, the influence of the settlement on pipeline stress in various key parts of the natural gas station was analyzed. The test results show that when the valve piers of the ground pipeline at the natural gas station settled, there were three stress concentration zones—inside the fixed piers at the left and right ends and near the settlement point—and the maximum stress occurred inside both ends of the fixed piers. When the pipeline settlement occurs, it is necessary to pay attention to the key parts, such as the fixed foundation pier at the left and right ends, the settlement point, the reducing tee, and the elbow. The strain test system can be adopted to monitor the stress of the pipelines and equipment in the settlement-prone area, which displayed the strain and stress state of the tested pipeline section in real time and realized the informatization of the pipelines’ health status in a natural gas station. Those results can provide a basis for the safety assessment of pipelines given the foundation settlement action in a natural gas station.