地下管线的轴向动态失稳分析

本文基于实际震害，提出了地下管线两类轴向动态失稳模型──梁型动态失稳模型和壳型动态失稳模型，并对两类失稳现象进行了分析。模型将地下管线分别假定为埋于弹性半无限空间中的长梁和圆柱薄壳，土－管线相互作用采用平面动应变与静态Ｍｉｎｄｌｉｎ解相结合的方法求得。最后，以我国实际的城市地下煤气管线和长距离输油管线为例进行了参数研究，得出了一些有益的结论，解释了震害的成因。

DYNAMIC INSTABILITY OF BURIED PIPELINES IN AXIAL DIRECTION

Based on disasters due to earthquake, two model-beam-type dynamic instability and Shell-type dynamic instability for two types of dynamic instability of buried pipelines in axial direction are put forward,and equation for the dynamic instability of buried pipelines are established. The models regards the pipeline as long beam and circular cylindrical thin shell buried in elastic half-space. The soil-pipeline interaction is obtained by combining the dynamic plane strain solution with the static Mindlin solution. Taking buried gas pipelines in city and long oil-pipelines in our country as examples, parametric studies are carried out,and some conclusions are obtained, and reasons for disasters are explained.