液化场地埋地钢管地震易损性分析  

Seismic Vulnerability Analysis of Buried Steel Pipes at a Liquefaction Site

作　　者：梁泽田 郑山锁[1,2] 刘晓航 吴星霞 杨丰 Liang Zetian;Zheng Shansuo;Liu Xiaohang;Wu Xingxia;Yang Feng(School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China;Key Lab of Structural Engineering and Earthquake Resistance,Ministry of Education(XAUAT),Xi’an 710055,China;China Qiyuan Engineering Design and Research Institute Co.,Ltd.,Xi’an 710018,China)

机构地区：[1]西安建筑科技大学土木工程学院,西安710055 [2]西安建筑科技大学结构工程与抗震教育部重点实验室,西安710055 [3]中国启源设计研究院有限公司,西安710018

出　　处：《天津大学学报（自然科学与工程技术版）》2023年第1期55-63,共9页Journal of Tianjin University：Science and Technology

基　　金：国家重点研发计划资助项目(2019YFC1509302);国家自然科学基金资助项目(52278530);陕西省重点研发计划资助项目(2021ZDLSF06-10);西安市科技计划资助项目(2019113813CXSF016SF026).

摘　　要：位于地震活动区液化场地环境中的埋地钢管,除了需要长期面临地震灾害的威胁以外,还易受到土层液化所产生的浮力作用,从而发生严重破坏导致区域的正常使用功能中断.为了开展液化场地环境中埋地钢管的地震易损性研究,采用了Matasović非线性本构模型并结合经Byrne修正的Martin孔压增量模型描述土体的非线性特性及液化特性,基于ABAQUS有限元分析平台开发了相应的液化砂土UMAT程序,并通过建立与振动台实验相应的数值模型验证了其在有限元模拟中的分析可靠性;结合实体非线性接触模型和壳体-等效土弹簧模型的特点创建了管土接触-土弹簧数值模型并进行了埋地钢管增量动力时程分析,从而建立了不同液化区长度、不同埋深条件下钢管地震响应的需求模型,结合管道破坏状态的划分和从概率意义上确定的各极限损伤状态限值对3种不同液化区长度及3种不同埋深钢管分别进行了地震易损性分析,建立了液化场地钢管损伤指标与地震动强度指标之间的解析易损性模型,并进一步绘制了对应的易损性曲线.结果表明:在相同地震动强度作用及相同埋深条件下,液化区长度越长,埋地钢管的各极限破坏状态下超越概率越大;在相同地震动强度作用及相同液化区长度条件下,埋深越大,埋地钢管的各极限破坏状态下超越概率也越大.Buried steel pipes located in the liquefaction site environments in seismically active areas are subject to the long-term threat of seismic hazards and vulnerable to the buoyancy forces generated by the liquefaction of soil layers.Moreover,they suffer severe damage,thereby disrupting normal regional functions.To conduct the seismic vulnerability research of buried steel pipes in a liquefaction site environment,nonlinear and liquefaction characteristics of the soil were described using the Matasovićnonlinear constitutive model combined with the Martin pore pressure increment model modified by Byrne.Additionally,based on the ABAQUS finite element analysis platform,the corresponding UMAT program for liquefied sandy soil was developed,whose analytical reliability in finite element simulations was verified by establishing numerical models corresponding to the shaking table experiments.Combining the characteristics of the solid nonlinear contact model and the shell-soil spring model,a numerical model of the pipe-soil contact-soil spring was created,and incremental dynamic analysis of the buried steel pipe was performed to establish the demand model of the seismic response of the steel pipe under different liquefaction zone lengths and burial depths.Combining with the classification of damage states and the ultimate damage state limits determined in a probabilistic sense,the seismic vulnerability analysis of buried steel pipes was performed,thus establishing the analytical vulnerability models of buried steel pipes at the liquefaction sites with three different liquefaction zone lengths and three burial depths.The relationship between the pipes damage index and the ground motion intensity index was characterized.In addition,the corresponding vulnerability curves were drawn.The results demonstrated that the longer the liquefaction zone,the greater the probability of exceeding each limit damage state of the buried steel pipe under the same ground motion intensity and burial depth;the greater the burial depth,the greater

关 键 词：液化场地 埋地钢管 UMAT 管土接触 地震易损性分析 

分 类 号：P315.9[天文地球—地震学]