基于突变和模糊理论的重力坝坝基失稳概率计算方法研究

风险分析在高混凝土重力坝稳定安全评价方面的有效应用尚处于发展阶段，在风险分析的框架内研究重力坝坝基失稳概率的计算理论与方法是一项基础性研究。本项目基于突变理论和模糊理论研究高混凝土重力坝模糊-随机失稳概率计算方法，研究内容包括：采用三维弹塑性有限元法研究混凝土重力坝坝基滑移失稳突变判据，构建坝基失稳概率计算功能函数，论证塑性应变能突变失效准则的模糊化处理原则与方法，建立包含随机性、模糊性等不确定性因素的坝基失稳概率计算模型，从数学、力学原理上研究获得简便、高效、准确的失稳概率计算方法与求解途径。研究成果为高混凝土重力坝风险评估与决策提供重要指标与研究思路，进而有益于重力坝失事安全预警与风险控制。

The application of risk analysis methodology keeps developing in stability evaluation of foundation of high concrete gravity dams nowadays. It is a key point and complex problem about the theory and calculating method of instability probability of a gravity dam in risk analysis. A new methology of calculation on fuzzy stochastic instability probability is provided on the basis of catastrophe theory and fuzzy theory. Firstly, the catastrophe failure criteria by plastic strain energy computing is analyzed using 3D elastic-plastic FEM, and then the fonction on instability probability of dam foundation is suggested. The fuzzy processing method about failure criteria is also discussed and a mathematic model of instibility probablility calculating considering two types of uncertainty, such as randomness and fuzziness, is set. Finally, a serial of programming codes are made by simplify, effective,and accurate algorithms. The work will promote new means for risk evaluation and decision-making for the instability problem of high concrete gravity dams.