| 摘要: |
| 地震液化数值分析方法的可靠性验证研究是开展实际工程液化安全评价的前提条件。采用基于up形式的Biot动力固结方程的非线性有限元程序GEODYNA，对液化试验和分析项目（LEAP）中的饱和斜坡地基离心机模型试验进行了动力弹塑性有效应力数值分析，其中土体采用改进的广义塑性模型。结果表明：数值模拟的加速度反应谱和加速度时程与试验数据基本吻合；数值模拟再现了试验中孔隙水压力的累积、发展和消散规律，并再现了循环剪切作用下土体应力路径的发展规律和土体的剪胀现象；数值模拟合理地反映了残余变形的累积发展过程，并且数值模拟得到的地基变形分布规律与试验规律相符，变形量值也基本在试验的包线内。研究成果验证了该地震液化分析方法的可靠性，可以为工程液化安全评价提供有效的数值分析方法。 |
| 关键词: 液化 数值分析 孔隙水压力 离心机模型试验 |
| DOI：10.12170/201906013 |
| 分类号:TU435 |
| 基金项目:国家自然科学基金资助项目（51890915,U1965206,51679029） |
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| Numerical analysis of a liquefiable slope ground and its centrifuge model test verification |
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ZOU Degao1, TENG Xiaowei1, LIU Jingmao1, WANG Feng2, LIU Xin3
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1.School of Hydraulic Engineering, Faculty of Infrastructure Engineering, Dalian University of Technology, Dalian;2.Power China Chengdu Engineering Corporation Limited, Chengdu;3.State Key Laboratory of Nuclear Power Safety Monitoring Technology and Equipment, China Nuclear Power Engineering Co., Ltd., Shenzhen
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| Abstract: |
| It is necessary to verify the reliability and rationality of a liquefaction numerical analysis method before its application to engineering safety assessment. In this study, the nonlinear finite element procedure GEODYNA based on up form Biot dynamic consolidation equations and the generalized plastic model of liquefiable soil modified by Dalian University of Technology are used to conduct a dynamic effective stress analysis of the centrifuge model test in the liquefaction experiment and analysis project (LEAP). The results show that the acceleration response spectrum and the acceleration time histories computed by the numerical method are basically consistent with the experimental data. The accumulation, development and dissipation principle of the excess pore pressure in the centrifuge model test are well reproduced by the numerical simulation. The development of soil stress paths and the soil dilatancy effect under cyclic shear loading are generally captured in the simulation. The accumulation and development process of residual deformations is reasonably reflected by the numerical simulation and the deformation distributions of the slope ground obtained by the numerical simulation are in good agreement with the test data. The reliability of the liquefaction numerical analysis method employed is verified, which ensures that it shall become an effective numerical method for engineering liquefaction safety assessment. |
| Key words: liquefaction numerical analysis pore pressure centrifuge model test |
