【作者】 冯艺；

【导师】 严驰；

【作者基本信息】 天津大学 ， 岩土工程， 2004， 硕士

【摘要】 土坡稳定分析是土力学的经典课题。并且，随着土工合成材料在道路工程中的广泛应用，加筋土坡的稳定分析成为一个重要研究课题。目前，在工程实践中大多采用极限平衡法，但极限平衡法不考虑土体的应力—应变关系以及加筋对土体中应力分布的改变，因此临界滑动面上的应力状态与实际不符。本文采用非线性有限元方法来分析加筋土坡的应力场和位移场，并将有限元计算应力结果用来确定临界滑动面和相应的安全系数。土体的本构关系采用Duncan-Chang模型，土工合成材料看作是一种不能受压只能受拉且抗弯刚度为零的柔性材料，筋土之间设置接触面，接触面单元采用Goodman单元。土坡稳定安全系数定义为滑动面上抗剪强度与剪应力的比值，临界滑动面的搜索采用动态规划法。本文利用有限元方法分析了不同地基土坡在不同位置加筋对应力场、位移场、临界滑动面和安全系数的影响。在有限元分析基础上的稳定分析方法，由于模拟了土体的应力—应变特征和土坡的填筑过程，明显优于极限平衡法。更多还原

【Abstract】 The field of soil mechanics is a classical topic. With the using of geosynthetics, the stability analysis of geosynthetics reinforcement slope becomes more important. The analysis of slope stability in engineering practice has been made dominantly with Total Stress Analysis methods up to nowadays, but as a matter of fact in most cases the state of stress on critical slip surface is not in agreement with that of real ones, as the Total Stress Analysis methods only consider the integral unit stress of soil mass, take no account of the distributing of stress and the relationship between stress and strain.In this paper, the nonlinear finite element method is to be used to analyses the stresses field and displacements field of geosynthetics reinforcement slope, and the result that calculated by the finite element method program is used to search the critical slip surface and decided the safety factor. Duncan-Chang nonlinear numerical model and Goodman interface elements are used in this program. The safety factor is determined by the ratio of the summed shear to the summed shear stress along the critical slip surface. The dynamic programming method is adopted in searching for the critical slip surface of a slope.The stresses and displacements field of various geosynthetics reinforcement slopes are analyzed in this paper. It is this result that indicates that the advantages of these tow methods based on finite element technique to limit equilibrium methods is quite obvious, as the finite element method rather than traditional limit equilibrium method can simulate the behavior of stress and strain of soils and the processes of slope formation and /or excavations.更多还原