【作者】 向俐蓉；

【导师】 张建海；

【作者基本信息】 四川大学 ， 岩土工程， 2003， 硕士

【摘要】 重力坝基础的稳定性问题历来都是设计和地质专家关注和重视的问题。百色重力坝地质条件复杂，地基岩体具有高模量比、节理裂隙发育等不良地质现象。百色重力坝的稳定性是事关工程成败的关键技术问题。本文结合正在进行的百色工程的科研项目“百色RCC重力坝主坝基础静动力稳定性分析”，综合运用三维非线性有限元及三维刚体弹簧元仿真计算方法，对百色RCC重力坝的主坝基础稳定性及其失稳过程和失稳机理展开了系统的研究工作。 1、对有限元前处理作了改进，实现了有限元前处理工作的可视化和流程化等，实现了在Visual FORTRAN中对AutoCAD的直接调用和控制，实现了对三维规则体的自动剖分。 2、根据百色的地形地质条件，充分模拟了蚀变带、节理裂隙、F6断层、灌浆帷幕等，较为真实地建立了坝体与地基相互作用的整体三维数值模型；采用有限元法对坝体及坝基在不同工况下的应力应变状态开展分析，评价各工况下坝基的运行状态；而后采用超载法和综合法对大坝稳定性进行分析，模拟坝基的渐进性破坏过程，从而得到坝基在超载和强度下降过程中的破坏模式和破坏发展路径，最终确定坝基超载安全系数和综合安全系数。 3、在坝基稳定性有限元分析成果基础上，拟定多条滑移路径，用刚体弹簧元法进行静动力分析，找出在静力以及地震工况下最危险滑移块体和滑移路径。 4、改变地基弹模组合及渗透作用方式做应力应变敏感性分析。 5、收集其它重力坝的位移值并与之比较。更多还原

【Abstract】 Stability of Gravity dam is always of great concern to designer and geological expert. The foundation of Baise gravity dam has bad geological phenomena such as high elastic modulus ratio, joint fissures and large faults etc., so stability of Baise gravity dam is the essential technical problem to project’s success. In this thesis 3D non-linear FEM (Finite Element Method) and 3D RBSM (Rigid Body-Spring Model) are used to conduct the following research work:1. The mesh generation program of FEM is improved in the aspects of visualization and systematization.2. According to the geological conditions of Baise project, erosive bands and joint fissures, F6 fault and grout curtain are fully simulated to establish 3D numerical model of the dam and its foundation. 3D non-linear FEM is used to analyze the stress and strain and to appraise the operation state of both the dam and it’s foundation under different operation conditions. By overloading the upstream water level and reducing rock strength parameter, the dam foundation’s degradation process is simulated and the damage pattern and paths are determined, and finally the safety factor is determined.3. Based on the results of dam foundation’s FEM stability analysis, possible sliding paths are supposed and 3D RBSM is used to find out most dangerous sliding bodies and sliding paths under static and seismic operating conditions.4. Sensitivity analysis of stress and strain under different elastic modulus combinations of dam foundation, different water levels, different seepage conditions is also conducted.5. Displacements of other gravity dams are collected and compared with the results of Baise project.更多还原