为研究极值理论在大坝变形监控指标拟定上的计算方法,先阐述了极值理论中BMM模型和POT模型的计算原理,并利用对数似然函数实现参数估计;然后采用超均值函数图法选取POT模型的阈值,结合大坝失事概率拟定监控指标。工程实例分析表明,极值理论在大坝变形监控指标拟定中有效可行,精度较高。 In order to study the calculation method of extreme value theory in dam deformation monitoring index formulation, the calculation principle of BMM model and POT model in extremum theory is expounded first, and the parameter estimation is realized by using log-likelihood function. Then, The method chooses the threshold of POT model and formulates the monitoring index according to the probability of dam failure. The engineering example shows that the extremum theory is effective and feasible in the formulation of dam deformation monitoring index with high accuracy.