长河坝水电站施工期临时度汛挡水风险度分析

摘要

Filling construction of Changheba Hydropower Project has lagged far behind of schedule at the end of 2013, causing problems for the temporary flood-passing scheme design and safety evaluation during construction period. According to the two possible cases of dam and cofferdam retaining water, the water retaining risk model for temporary flood-passing during construc-tion period was built. Considering the randomness of hydrologic, hydraulic factors, capacity, and monthly dam average rising speed, the Monte-Carlo method was used to measure the risk. According to analysis and calculation, it is concluded that the risk model and the calculation method is feasible and effective, which can provide important reference information for the dam fill-ing plan and safety evaluation during construction period.%2013年底长河坝水电工程坝体填筑进度严重滞后，给施工期临时度汛方案的制定及安全评估带来了困难。针对可能存在的坝体或围堰挡水2种情况，构建了施工期临时度汛挡水风险数学模型。综合考虑水文、水力、库容等因素的随机性，以及坝体填筑月平均上升速度，采用Monte-Carlo方法测度挡水风险。计算分析结果表明，风险模型及计算方法准确有效，为施工期填筑计划安排及安全评估提供了重要参考信息。