摘要
为分析高耸建(构)筑物在爆破拆除下塌落体触地冲击载荷对浅埋高密度聚乙烯(HDPE)燃气管道的损伤状况,借助Abaqus软件建立了塌落体-管道-土接触模型,研究了HDPE管道在塌落冲击载荷下的力学响应,分析了触地速度、管道壁厚、回填土压实度、触地方式、触地偏心距对燃气管道应力及变形的影响规律。结果表明,塌落体触地冲击下管道出现应力峰值时间极短,管道应力与形变量沿轴向减小;管道横截对称面处的最大Mises应力随触地速度增大而增大,随壁厚增大而减小;回填土的压实度对管道的安全运行有较大影响;棱边触地方式下的管道最大Mises应力最小,越是形状不规则的塌落体引起的管道应力峰值越小;距离塌落区中心越近的管道越容易因达到强度失效极限而出现损伤。
Via a kind of nonlinear finite element software known as the ABAQUS,the present paper tries to restore the process of the slump body impacting the buried pipeline.To ensure the safety and smoothness of the gas transportation through a shallow buried high-density polyethylene pipeline,it is necessary to assess and analyze the likely damage risk to be caused by the demolition blast of the urban structure.To achieve the goal,we have,first of all,built up a soil and pipe-soil contact mode by defining the unit type and the real constant that has been meshed in the geometric model so as to work out a finite element model respectively for the collapse.And,then,the variation of the stress and deformation of the polyethylene gas pipe has to be analyzed with the impact velocity,the pipe’s wall thickness,the compact of the backfill,the contact method and the offset distance.The results can then indicate that the peak stress fluctuation time of the pipe should be extremely brief.The stress and deformation of the buried gas polyethylene pipe should be decreasing in the axial direction of the pipe.What is more,the highdensity polyethylene gas pipe may exhibit an increase in the maximum Mises stress with the various areas of cross section of the pipe with an increase of the impact velocity,for it has an approximate linear relation,in case the stress is decreasing with the increase of the wall thickness.On the other hand,the compaction of the backfill has a great influence on the safety operation of the shallow buried gas pipeline.At this moment,the maximum Mises stress of the pipe would be minimized when the edge of the slump body is getting to collide with the ground.The more irregular the shape of the slump,the less the maximum Mises stress of the gas pipeline.The area near the impact zone can be found to reach a strength failure limit likely due to the gas high-density in the pipeline.The research of this paper can thus provide valuable reference for the safety protection of the above said highdensity polyethylene gas pipeline.
作者
张鹏
安兆暾
ZHANG Peng;AN Zhao-tun(School of Civil Engineering and Architecture,Southwest Petroleum University,Chengdu 610500,China)
出处
《安全与环境学报》
CAS
CSCD
北大核心
2020年第6期2123-2130,共8页
Journal of Safety and Environment
关键词
安全工程
HDPE燃气管道
塌落触地载荷
力学响应
数值模拟
safety engineering
high density polyethylene gas pipeline
collapsed load
mechanical response
numerical simulation
