横向非一致地震激励下埋地管道的动力响应分析

Dynamic response analysis of buried pipelines under transverse non-uniform seismic excitation

为研究埋地管道在地震激励时管-土相互作用的动力响应问题,研发双向层状剪切连续体模型土箱,建立管-土相互作用有限元分析模型,对横向非一致地震激励下埋地管道地震响应进行数值模拟分析,并与试验结果进行对比。结果表明:数值模拟和振动台试验结果中的管道应变峰值均呈现出沿管道中间大两端小的现象,管道中间应变峰值最小达到两端的1.6倍左右;管道加速度、土体加速度峰值均随着加载等级的提高而增大,涨幅愈加明显,多峰频率由0~10 Hz逐渐向10~20 Hz频域扩散,管道运动更为自由;土体位移随着加载等级的提高呈现逐级增大的现象,在加载等级增加到0.4g时位移曲线斜率减小,土体非线性表现明显。数值模拟和振动台试验对比分析的结论表明数值模拟分析的合理性和试验结果的可靠性,为研究横向非一致激励对埋地管道地震响应的影响提供了依据。

A bidirectional laminated shear continuum modeled soil box was developed,and a finite element analysis model of pipe-soil interaction was established to study the dynamic response of buried pipelines under seismic excitation.The seismic response of buried pipelines under transverse non-uniform seismic excitation was analyzed by numerical simulation,and the simulated results were compared with the test results.Results show that the peak strain of pipelines in the simulated and test results is large in the middle and small at two ends;the peak strain in the middle is at least 1.6 times that at two ends.The peak values of pipeline and soil acceleration increase with the loading level,the multipeak frequency gradually diffuses from the frequency domain of 0-10 Hz to 10-20 Hz,and the pipeline moves freely.The displacement of soil increases with the loading level;the slope of the displacement curve decreases when the loading level increases to 0.4g,and the nonlinear behavior of soil is observed.The conclusions show the rationality of numerical simulation analysis and the reliability of test results,thus providing a basis for studying the effects of transverse non-uniform excitation on the seismic response of buried pipelines.