论文部分内容阅读
地震工况下的坝坡抗滑稳定性核算一直是大坝安全性评价的重要环节,采用科学合理的计算方法是评价坝坡安全性的基本保证。本文从概率极限分析的角度探讨了坝坡稳定性可靠度分析的概率意义,提出了将地震发生当做概率事件的坝坡可靠度计算方法。为验证将地震超越概率纳入坝坡稳定分析中的合理性,本文通过两个典型算例和小浪底坝坡典型剖面的抗滑稳定性分析研究了坝坡在地震工况下的单一安全系数与可靠指标的变化规律。研究结果表明在坝坡稳定分析中引入超越概率计算所得结果与工程实际相符,与以往的将地震发生当做确定性事件计算方法相比,该方法显著提高了坝坡的可靠指标值;比较可靠指标与单一安全系数的取值标准显示出在坝坡稳定分析中合理地引入地震概率分析方法能够保证坝坡在地震和正常工况下有相近的可靠指标值。
The stability calculation of dam slope under seismic conditions has always been an important part of dam safety evaluation. Scientific and reasonable calculation method is the basic guarantee to evaluate the safety of dam slope. This paper discusses the probabilistic significance of reliability analysis of dam slope stability from the perspective of probability limit analysis and proposes a method to calculate the dam slope reliability considering the occurrence of earthquakes as a probability event. In order to verify the rationality of incorporating the probability of earthquake surpassing into the slope stability analysis, this paper studies the single safety factor and the reliability of the dam slope under seismic conditions by analyzing two typical examples and the stability analysis of typical sections of Xiaolangdi dam slope. Indicators of the law of change. The results show that the results obtained by introducing the exceedance probability in the stability analysis of dam slope are consistent with the engineering practice. Compared with the traditional method of calculating the event of certain events, this method significantly improves the reliable index value of the slope; Compared with the reliable index The criterion of single safety factor shows that the reasonable introduction of seismic probability analysis method in the stability analysis of dam slope can ensure that the dam slope has similar reliable index values under earthquake and normal conditions.