ABSTRACT
Submarine pipe-in-pipe systems (PIP) are often subjected to high temperature, high pressure, or other external loads such as seismic loads. When an earthquake occurs, the simultaneous action of multiple loads will cause serious damage to the pipeline. Moreover, local initial defects often occur in pipes during manufacture, installation, and operation. The existence of initial defects will greatly increase the possibility of pipeline damage under load. The purpose of this paper is to analyze the buckling behavior of PIP under high temperatures and pressure and consider the seismic load caused by earthquakes. Based on the finite element software ANSYS, the buckling failure of the pipeline with initial defect under combination loads is simulated by using the time-history dynamic analysis methods. It was found that the seismic load will increase the pipeline buckling response and the maximum stress of the pipeline. Moreover, pipeline buckling failure is greatly affected by different insulation materials and initial defects.
