【摘要】 重力坝的深层坝基存在多个断层时,可能存在多个潜在的滑移路径。采用非线性有限元和传统的整体安全系数法计算各断层抗滑稳定的安全系数,并采用强度折减法可找到其最可能的失效路径。研究表明,强度折减系数大于各断层抗滑稳定的安全系数。基于加权响应面法,计算了各断层抗滑稳定的可靠指标,并与安全系数进行了比较,表明其安全系数与可靠指标并非存在完全的对等关系。将滑移路径中的各断层视为并联体系,各滑移路径组成串联体系,采用逐步等效线性化计算各滑移路径失效的可靠指标及深层抗滑稳定的体系可靠指标,计算结果与强度折减法基本一致,因此,在重力坝深层抗滑稳定的安全性评价中引入可靠度理论可弥补单一安全系数法存在的不足。更多还原

【Abstract】 Various potential sliding paths should be considered in the stability analysis of gravity dam against deep sliding when several faults exist in foundation.The safety factor of every fault calculated by utilizing nonlinear finite element method and the entire safety factor method,and the most possible sliding path was obtained by strength reduction method.The results indicate that the strength reduction factor is larger than the safety factors of all the faults.Based on the weighted regression response surface method,the reliability indexes of the faults were computed and compared with the safety factors.The result shows that there is no entire equity relationship between the reliability index and safety factor.Each failure mode of sliding path is a parallel system of several faults,and the final failure mode is the serial system composed of all sliding paths.The reliability of every sliding path and the final system were analyzed by means of the gradual equivalent linear method,and the results are consistent with the strength reduction factor.It is concluded that the reliability analysis can be applied to the safety evaluation of deep sliding stability of gravity dams to improve the shortcomings of the safety factor method.更多还原