南水北调中线交叉建筑物洪水风险估算模型研究

Research on flood risk estimation model of cross structures in Middle Route Project of South-North Water Diversion

南水北调中线工程运行阶段的风险是工程管理者关注的焦点之一。以往的研究只单纯考虑水文不确定性或工程结构不确定性,研究结果也只提供交叉建筑物在其设计基准期内的风险概率,不能给出不同洪水条件下的工程风险,对运行阶段的风险管理意义不大。通过综合考虑水文不确定性和工程结构不确定性,提出适用于交叉建筑物在各种洪水条件下的失效风险计算模型,该模型可以给出交叉建筑物在各种洪水条件下的失效风险。以河南省境内湍河梁式渡槽为例,建立渡槽失效故障树以及各种失效模式的极限状态,给出了一套可适用于渡槽水毁失效风险估算的方法。

The risk in operation period of the middle route project of South-North Water Diversion is a concerned issue for the project administrators.The previous studies only involve uncertainty of hydrological conditions or engineering structures,therefore,the results can give the risk probability of cross structures in design reference period;however,the risk probability under different flood condition can not be given,which has no remarkable significance for risk management in operation period.Through comprehensive consideration on hydrological and structural uncertainty,a failure risk model for cross structure,which can calculate the failure risk of cross structures under all flood conditions,is proposed.The model is applied to a large aqueduct project in Henan Province-Tuan River Aqueduct,and the fault tree and limiting state of various failure modes are established.The research provides a method for estimating risk of the aqueduct resulted from flood.