走滑断层作用下埋地充液钢质管道接口应变特性的试验

摘要

目的 研究走滑断层作用下埋地充液管道不同接口的力学性能,保证埋地管道的安全运行,并为埋地管道抗震设计提供参考.方法 利用自行研发的场地变形模拟箱体和千斤顶等设备,对走滑断层作用下埋地管道不同接口的力学性能进行试验.将接口形式分为焊接、螺纹连接、法兰连接,接口位置分别在断层处与非断层处(距离断层处500 mm)的管道埋于箱体内,并向管道内充入常温自来水,保持管内压力,再利用试验设备模拟走滑断层作用.结果 通过测量管道各处应变,箱体及管道位移和管内水压变化,得出只有焊接接口应变比相同位置直管段应变小;管道上最大应变出现在断层附近(试验中为距断层300 mm处);与螺纹连接管道相比,当断层错动量小时,焊接管道在断层处位移大,而断层错动量大时管道位移小;只有法兰连接管道内的水压有所下降.结论 走滑断层条件下,埋地管道接口适合用焊接,不适合用法兰连接;埋地管道接口在断层错动量小时适合采用螺纹连接,错动量大时适合采用焊接;在断层两侧一定距离处管道最容易破坏,埋地管道接口不宜设在此处.%The purpose of this paper is to study the mechanical performance of different joints of buried pipeline with liquid-filled under the action of strike-slip fault,which is the basis for ensuring the safe operation of buried pipelines and provides reference for seismic design of buried pipelines.The mechanical properties of different joints of buried pipelines under the action of strike-slip fault were simulated by using the experimental box,jack device and so on.The joints types were welded,screwed and flanged.Also,the joints locations were different,which were at the fault and the non-fault(500 mm from the fault)respectively.These pipelines were buried in the experimental box,and were filled with water at room temperature,which maintained the inner pressure.Then strike-slip fault movement was simulated by using the test equipments.By measuring the strain,the displacement of the box and the pipe,the water pressure within the pipe,it is found that only the strain at the welded joint is smaller than the straight pipe at the same position.The maximum strain of the pipeline happens near the fault (300 mm from the fault here).Compared with the screwed connection pipeline,the welded pipeline has a large displacement when the fault displacement is small,but the displacement of pipeline is small when the fault displacement is large.And the pressure drop is only in the flanged pipe.Under the strike-slip fault,the buried pipeline joint is the most suitable for welded,and not for flanged connection.The joint is suitable for screwed connection when the fault displacement is small.The pipeline would be damaged most possibly at a certain distance on both sides from the fault,in which the joints should not be located.