走滑断层位错作用下城市地铁隧道损伤分析

发布时间：2018-05-12 13:48

本文选题：地铁隧道 + 走滑断层　；参考：《岩土力学》2014年S2期

【摘要】：为了能够较快速、较准确地估计出穿越活断层城市地铁隧道的抗震薄弱部位,基于拟静力弹塑性有限元方法,以北京地铁7号线工程的区间隧道作为研究对象,采用数值模拟的方法研究了在走滑断层位错作用下地铁隧道的非线性反应。通过在数值计算模型中嵌入合理的损伤塑性本构模型,利用损伤指标研究了走滑断层下衬砌结构的破坏形式,重点分析了结构损伤的开始部位、发展过程以及最终的损伤程度,并建立了能够估计结构损伤范围及破坏最严重位置的统计关系式。结果表明,在走滑断层作用下衬砌结构出现损伤的区域主要发生在活断层附近一定范围内,拱腰部位的损伤最为严重;增加基岩上覆土层厚度能够减轻衬砌结构的破坏程度,当基岩上覆土层厚度大于等于临界覆盖土层厚度时可以不考虑走滑断层断裂对于浅埋隧道的影响。衬砌结构损伤区域长度与震级的大小和土层厚度有关,损伤最严重的位置随土层厚度的变化而改变。研究成果为穿越活断层地铁隧道的抗震设计和安全性评价提供了参考依据。
[Abstract]:In order to estimate the seismic weakness of subway tunnel through active fault city more quickly and accurately, based on the pseudostatic elastoplastic finite element method, the section tunnel of Beijing Metro Line 7 is taken as the research object. The nonlinear response of subway tunnel under the dislocation of strike-slip fault is studied by numerical simulation. By embedding a reasonable damage plastic constitutive model into the numerical calculation model, the failure form of the lining structure under the strike-slip fault is studied by using the damage index, and the starting position, the development process and the ultimate damage degree of the structure damage are emphatically analyzed. A statistical relation is established to estimate the damage range and the most serious damage position. The results show that the damage area of the lining structure under the action of strike-slip fault mainly occurs in a certain range near the active fault, and the damage at the arch waist is the most serious, and the damage degree of the lining structure can be reduced by increasing the thickness of the overlying layer on the bedrock. The influence of strike-slip fault on shallow tunnel can not be considered when the thickness of overlying layer of bedrock is greater than that of critical overburden. The damage area length of lining structure is related to the magnitude and the thickness of soil layer, and the location of the most serious damage changes with the change of soil thickness. The research results provide a reference for seismic design and safety evaluation of subway tunnel through active fault.
【作者单位】：中国地震局工程力学研究所地震工程与工程振动重点实验室;东北林业大学土木工程学院;
【基金】：“十二五”国家科技支撑计划项目(No.2012BAK15B02-01)
【分类号】：U452.28

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