考虑压缩失效时埋地管线跨地震断层的最佳交角研究

在断层错动下埋地管线跨断层的最佳交角研究方面,已有方法均以管道受拉失效为基本假定,未考虑管道压缩失效的情况.本文利用管体壳模型有限元方法进行了跨断层管线在断层错动下管体反应的计算分析,在考虑管材特性、管道尺寸及地基土特性多种影响因素的情况下,探讨了在仅控制轴向拉伸应变值和同时控制轴向拉伸应变值与轴向压缩应变值两种管道失效控制准则下管道的失效问题,分析了不同失效控制准则对管线跨断层的最佳交角的影响.发现失效控制准则是确定最佳交角值的关键因素,而且基于同时考虑拉伸和压缩失效的控制准则,管线跨断层的最佳交角应在70°左右.

Study on the Best Crossing Angle Between Pipeline and Fault Considering Compression Failure of Pipe

The basic assumptions of existing approaches are that the pipelines fail in tension crack of pipe for studies on the best crossing angle between pipeline and fault,but they do not consider the cases of pipeline failures induced by the compression crack or buckling of pipe.In this paper,some case studies are made by the finite element method with shell model of pipe,in which the different material behaviors of pipe,dimensions of pipe and properties of surrounding soils are taken into consideration.Based on the results of case studies,the failure problems of pipelines are discussed under different rules of failure control of pipes which are the rules of only controlling the tension failure of pipe or controlling both the tension failure and the compression failure of pipe,and the influences of the different rules of failure control are analyzed on the best crossing angle between pipeline and fault.The opinions are obtained that the rule of failure control is an important factor to bring out the best crossing angle between pipeline and fault,and the best crossing angle should be about 70 degrees under the rules of controlling both the tension failure and the compression failure of pipe.