Numerical Simulation Of Buried Pipeline Damage Under Dynamic Loading

The buried pipeline's damage under dynamic loading is analyzed through numerical simulation method on the basis of Automatic Dynamic Incremental Nonlinear Analysis (ADINA). Influencing factors of buried pipeline's damage and numerical modeling are investigated. Complex site conditions, fault and fluid-pipe coupling are considered.Considering soil-pipe interaction, Boolean operator is used to merge site and pipe, and site-pipe physics contact is solved through soil-pipe friction. As the importance and particularity of fault to buried pipeline's damage, further investigations of buried pipeline damage crossing fault analyze. The preferences are analyzed, pipe's parameters such as depth, thickness, pipe diameter, and mechanical property of material; soil parameters such as soil types, internal friction angle, pipe-soil interaction; fault's parameters such as fault types, fault throw, fault drop, fault-pipe angle, mechanical property of material; load types such as gravity force, linear displacement load, seismic load and seismic wave. Some conclusions are drawn from the calculating results: when buried pipes cross fault, pipe's embedded depth should be shallow, and big pipe diameter and thick wall should be selected. Avoid the site where fault moves severe, and select suitable pipe-fault angle. Bigger pipe-soil friction coefficient is helpful for buried pipe crossing fault. Under dynamic loading, buried pipe would first damaged in compressive region of bilateral fault, so special treatment should be done to pipe in bilateral fault region.Buried pipeline's damage under fluid-structure interaction is analyzed through ADINA-FSI with conveying medium and velocity in consideration. The conveying medium in pipe has great effect on buried pipeline's damage, its flow pattern, temperature, pressure change, velocity, all of these can influence the shell of pipe and its stress distribution. So it is very important to analyze the fluid-pipe coupling. The bigger the density and velocity of the fluid in pipe, the worse the pipeline's damage. So when buried pipe is designed, density and velocity of the fluid in pipe should be generally considered.