滑坡灾害典型受灾体失效概率计算方法及应用

从系统研究的角度看,滑坡灾害系统包括致灾体子系统和受灾体子系统。滑坡灾害是这2个子系统共同作用的结果。以往的研究主要集中在致灾体稳定性的评价上,没有全面考虑2个子系统对灾害风险的影响,尤其缺少对受灾体子系统的研究。针对这种现状,对一种典型受灾体（框架结构）在滑坡灾害作用下的失效概率计算方法进行探讨：将滑坡灾害致灾模式简化为致灾体对受灾体的冲击破坏模型,推导了滑坡冲击力计算公式;探讨了典型受灾体整体功能函数的建立方法,提出了滑坡灾害典型受灾体失效概率计算方法。采用该方法进行了算例分析,分析了滑坡灾害致灾强度和受灾体抗灾性能对受灾体失效概率的影响,得出滑坡灾害影响范围可划分为绝对危险区域、相对危险区域和绝对安全区域。还研究了受灾体失效概率对不确定性影响因素的敏感性,得出当定值计算受灾体为失效时,受灾体失效概率随影响因素变异性增加而减小;当定值计算受灾体为安全时,受灾体失效概率随影响因素变异性增加而增加。

A Calculation Methed for Failure Probability of Typical Element at Landslide Risk

From the point of view of system theory,the landslide hazard system includes two subsystems： subsystem of hazard and subsystem of stricken.The consequence of landslide hazard is based on the interaction of these two subsystems.previous studies concenerate on evaluation of landslide stability.Hence,the study of a typical element at landslide risk is focused.And a method to calculate failure probability of typical element（frame structure） at landslide risk is discussed.Furthermore,the influences of both impact force and impact resistance-capability of element at risk on failure probability are analyzed,which shows that,for each elements at risk,the landslide impact area can be divided into absolutely dangerous zone,relatively dangerous zone and absolutely safety zone.In addition,with the condition that the structure failure probability is above 50%,as the variability of impact force increases,the structure failure probability decreases;with the condition that structure failure probability is below 50%,as the variability of impact force increases,the structure failure probability also increases.