基于快速连溃洪水计算的梯级堰塞湖风险分析  

Risk analysis of cascade landslide dam based on an approach of quick breach flood calculation

作　　者：陈淑婧 郑轩 王江波 张燕 于沭[3] CHEN Shujing;ZHENG Xuan;WANG Jiangbo;ZHANG Yan;YU Shu(National Academy for Mayors of China,Beijing 100029,China;China Nuclear Power Engineering Co.,Ltd.,Beijing 100048,China;China Institute of Water Resources and Hydropower Research,Beijing 100048,China)

机构地区：[1]全国市长研修学院,北京100029 [2]中国核电工程有限公司,北京100048 [3]中国水利水电科学研究院,北京100044

出　　处：《水利水电技术》2020年第3期82-90,共9页Water Resources and Hydropower Engineering

基　　金：国家自然科学基金项目“黄土高原淤地坝风险孕育机理与溃决仿真、预警分析及抗冲加固技术研究”(41731289)。

摘　　要：地震滑坡堵江作用形成的梯级堰塞湖,上下游单元之间存在级联效应,增大了溃决风险和成灾规模。及时合理的应急方案可以有效保证上下游的生命财产安全,然而现阶段缺乏快速定量的梯级堰塞湖的风险分析方法。以溃口洪水计算为核心,结合河道洪水演进计算和水库调洪计算,提出了一种梯级堰塞湖连溃洪水的快速计算方法,并应用至国内外第一个具有详细数据资料的梯级堰塞湖小岗剑梯级堰塞湖溃决实例中。定性分析了堰塞湖风险等级,使用提出分析方法进一步定量反演计算连溃洪水过程,评估了应急处置工程效果,分析不同组合状况下连溃洪水的规模。结果显示:反演计算其连溃峰值流量为3736 m 3/s,与实测值3950 m 3/s基本一致。当不开挖泄流槽时,连溃峰值流量高达4865 m 3/s,泄流槽降低梯级洪峰30%。快速定量连溃洪水计算可以辅助优化联合调度方案,是减轻连溃洪水灾害、保护流域整体安全的一种行之有效的非工程措施。研究结果可以为梯级堰塞湖定量风险评估以及应急除险预案制定提供理论依据。The cascade effect is there among the upstream and downstream ones of the cascade landslide dams formed by seismic landslides,which increases the dam failure risk and the disaster scale.The relevant in-time and reasonable emergency scheme can effectively ensure the upstream and downstream life and property safeties,but lack of fast quantitative risk analysis method is there for the cascade landslide dams at present.By taking dam-breach flood calculation as the core,a method for fast calculation of continuous dam-breach flood of cascade landslide dams is proposed herein in combination with river channel and reservoir flood routings,and then applied to the actual dam-breach case of the first cascade landslide dams——Xiaogangjian cascade dams with detailed data at home and abroad.The risk grade of the landslide dams is qualitatively analyzed,and then the further quantitative inversion is made on the continuous dam-breach flood process by means of the analysis proposed herein,while the effect of the emergency disposal works is assessed and the scales of the continuous dam-breach floods under the conditions of different combinations are analyzed as well.The results show that the peak value of the continuous dam-breach flood is 3736 m 3/s,which is basically consistent with the measured value of 3950 m 3/s.The peak value of the continuous dam-breach flood is to be as higher as 4865 m 3/s without the excavation of discharge chute,however,the cascade flood peak can be lowered by 30%with discharge chute.The fast quantitative calculation of the continuous dam-breach flood can assist to optimize the relevant joint scheduling scheme and then is a feasible and effective non-engineering measure to alleviate the disaster from the continuous dam-breach flood and protect the overall safety of the river basin concerned.The study result can provide theoretical basis for the quantitative risk assessment and the formulation of the emergency risk elimination plan for cascade landslide dams.

关 键 词：小岗剑梯级堰塞湖 梯级连溃洪水 风险分析 应急处置 反演分析 流量 四川汶川地震 

分 类 号：TV135.9[水利工程—水力学及河流动力学]