逆断层作用下埋地管道的模拟计算

Numerical Simulation of Buried Pipeline under Reverse Fault Action

文章基于应变的设计理念,采用壳单元等效边界模型,利用AN SYS软件实现了断层作用下埋地管道的抗震校核计算,并对断层作用下埋地管道的变形影响因素进行了分析,结果表明:断层错动量大小是影响管道变形的主要因素,管道的峰值应变随错动量的增加呈近似等倍数的线性增加;管道与断层交叉角度的不同会导致管道产生不同的失效形式,在倾角为75°的逆断层作用下,管道与断层交叉角度小于55°时表现为拉伸失效,交叉角度大于85°时表现为压缩失效;随着管道埋深的增加,管道的峰值拉伸、压缩应变均有所增加;提高管道壁厚可以使管道以较低的轴向应变为代价来吸收更多的应变能,因此提高管道壁厚可以降低管道的峰值应变。

Based on the concept of strain-based design, the article realizes the numerical simulation of a buried pipeline under reverse fault action with the FEA software ANSYS by using the model of shell elements with equivalent boundary. It implements the aseismic check of the pipeline and analyzes the pipeline deformation factors. The results show that the dislocation of reverse fault is the crucial factor of pipeline deformation and the peak strain of pipeline linearly increases approximately in equimultiple with the growth of the fault dislocation; Different failure modes will be produced because of different crossing angles between the pipeline and the reverse fault： under the action of reverse fault with 75° inclination angle it will be tensile failure with the crossing angle less than 55°and be compression failure with the crossing angle greater than 85°Both the peak tensile strain and compression strain of the pipeline increase with increasing pipeline depth; The pipeline with thicker wall could obtain a lower axial strain at the cost of absorbing more strain energy, therefore the peak strain of pipeline could be decreased by increasing wall thickness.