埋地管道三参量粘弹性边界地震模型及其动力响应研究  

Three-parameter viscoelastic boundary seismic model and dynamic response for buried pipelines

作　　者：吴静波 杜强 曾祥国[1] 李伟[1] 赵清龙 WU Jingbo;DU Qiang;ZENG Xiangguo;LI wei;ZHAO Qinglong(MOE Key Laboratory of Deep Earth Science and Engineering,College of Architecture and Environment,Sichuan University,Chengdu 610065,China;Communication and Information Technology Center of Southwest Oil&Gas Field Company,Chengdu 610051,China)

机构地区：[1]四川大学建筑与环境学院,深地科学与工程教育部重点实验室,成都610065 [2]西南油气田分公司通信与信息技术中心,成都610051

出　　处：《重庆理工大学学报（自然科学）》2022年第3期240-250,共11页Journal of Chongqing University of Technology：Natural Science

基　　金：四川省应用基础研究计划项目(13JC0277);四川大学创新训练项目(C2021117710)。

摘　　要：目前,地下工程地震模型边界普遍采用刚性边界和两参数粘弹性边界,一方面,刚性边界完全没有考虑边界上的能量交换;另一方面,两参数粘弹性边界采用的Kelvin固体模型无法描述松弛特性,即不能描述岩土完整的蠕变、松弛、回复的粘弹性特性。首先,从无限域岩土介质中截取土-结构的有限模型,并在截面的边界节点上施加Kelvin-Voigt固体元件,建立三参量粘弹性人工边界,并推导了边界的法向和切向等效参数。然后,利用有限元模拟了Lamb表面源问题和P波斜入射的波动问题,得到的位移数值解与(近似)理论解吻合良好,验证了三参量粘弹性边界的有效性。最后,针对江油地区的抗震设防要求,使用校正后的EI Centro波作为输入载荷,建立埋地输气管道的三参量粘弹性边界地震模型,研究了地震波输入角和管道埋深对管道动态响应的影响,获得了埋地管道关键位置的动力学响应规律。提供的方法和获得的数据对埋地输气管道的抗震设计、施工和安全运营具有参考价值。At present,the boundary of underground engineering seismic model generally adopts rigid boundary and two-parameter viscoelastic boundary.On the one hand,the rigid boundary does not consider the energy exchange on the boundary at all;on the other hand,the Kelvin solid model adopted by the two-parameter viscoelastic boundary can’t describe the relaxation characteristics,that is,it can’t describe the complete viscoelastic characteristics of rock and soil in creep,relaxation and recovery.Firstly,a finite model of soil-structure is intercepted from infinite geotechnical media,and Kelvin-Voigt solid elements are applied to the boundary nodes of the section to establish a three-parameter viscoelastic artificial boundary,and the normal and tangential equivalent parameters of the boundary are derived.Then,the finite element method is used to simulate the Lamb surface source problem and the fluctuation problem of P-wave oblique incidence.The obtained displacement numerical solution is in good agreement with the(approximate)theoretical solution,which verifies the validity of the three-parameter viscoelastic boundary.Finally,in view of the seismic fortification requirements of Jiangyou area,the corrected EI Centro wave is used as the input load.A three-parameter viscoelastic boundary seismic model of buried gas pipelines is established to study the influence of seismic wave input angle and pipeline depth on pipeline dynamic response,and then the dynamic response laws of key locations of buried pipelines are obtained.The provided methods and obtained data have certain reference value for the seismic design,construction and safe operation of buried gas pipelines.

关 键 词：地震载荷 埋地输气管道 三参量粘弹性边界 动态响应 数值模拟 

分 类 号：O327[理学—一般力学与力学基础]