摘要
受水沙耦合致灾作用,暴雨山洪灾害一般表现为山洪洪水灾害、山洪水沙灾害及山洪泥石流灾害3种模式,不同灾害模式的成灾特点、灾害规模、致灾指标及阈值常存在显著差异。传统暴雨山洪灾害防治预警技术的研究思路主要以“雨量-径流-成灾水位”雨水情分析为主,缺乏“雨-水-沙”变化系统研究,未充分考虑洪水泥沙耦合作用下山洪灾害易发区的成灾特征,尤其是超量泥沙补给造成的“沟床淤积-水位陡增”型山洪灾害极易漏警。结合金沙江支流中都河小流域和岷江支流白沙河小流域山洪灾害实地调查及分析,初步表明流域内山体滑坡形成的松散体是流域水沙运动的重要泥沙补给源,从而极易诱发暴雨山洪水沙灾害和山洪泥石流灾害。采用TRIGRS模型分析中都河小流域和白沙河小流域的滑坡易发性,将滑坡低风险区划为暴雨山洪洪水灾害预警区,对具有丰富固体物源的滑坡中、高风险区,根据陡缓衔接河段泥沙易灾区判别法划分为山洪水沙灾害和山洪泥石流灾害预警区。结合4种暴雨山洪洪水灾害预警方法,即洪水水位陡涨率判定法、实时累积雨量法、水位-流量反推法及简易雨量站广播预警法,分析中都河小流域典型暴雨山洪灾害预警区的预警指标,以基于河床冲淤变化的洪水位上涨率法确定白沙河小流域暴雨条件下山洪水沙灾害预警区的预警水位。结果表明:TRIGRS模型划分的滑坡风险区与中都河小流域和白沙河小流域滑坡、泥石流灾害调查较为吻合;中都河小流域滑坡风险较低,沿河村落均可划为山洪洪水灾害预警区;白沙河小流域下游滑坡风险较低的沿河村落可划为山洪洪水灾害区,中、上游为滑坡中、高风险区,其中,沟床陡缓坡衔接段划为山洪水沙灾害预警区,陡坡段划为山洪泥石流预警区。中都河小流域暴雨山洪灾害预警分析表明:水位-流量�
Flash flood disaster,especially affected by the coupling of flood and sediment,is categorized into at least three forms:water flood disaster,water-sediment flow disaster and debris flow disaster.There are significant differences in characteristics,scale and warning threshold of different disaster forms.The traditional research ideas of prevention and early warning techniques for flash flood disaster mainly depend on the“rainfall-runoff-stage”relationship,but lack of system consideration of interactions among“rainfall-runoff-sediment”and characteristics of flash flood disaster resulted from coupling of flow and sediment movement,and then an early warning of the disaster with“sediment deposition-water level sudden increase”due to excessive sediment supply is very easy to miss.According to the analysis and investigation,loose particles formed by landslides are the important source of sediment supply for water-sediment flow disaster in Zhongdu River basin and Baisha River basin,which are the tributaries of Jinsha River and Min River,the results indicate that the water-sediment flow disaster and debris flow disaster could be occurred,respectively.For this reason,the TRIGRS model(transient rainfall infiltration and grid based regional slope-stability model)was utilized to analyze the landslide susceptibility of basins,in that the low risk areas were divided into water flood disaster warning zones,the higher-risk areas with rich solid source into water-sediment and debris flow disaster warning zones according to riverbed morphology.Water flood disaster warning index can be calculated through four methods:rising rate of flood level,real-time accumulated precipitation,inversion on water level/flow and broadcast warning of simple precipitation station,in Zhongdu River basin.The method of rising rate of flood level based on riverbed deformation was used in the calculation of critical flood level for water-sediment flow disaster in Baisha River basin.The results indicated that landslide risk was low in the Zhongd
作者
王协康
杨坡
孙桐
许泽星
WANG Xiekang;YANG Po;SUN Tong;XU Zexing(State Key Lab.of Hydraulics and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China)
出处
《工程科学与技术》
EI
CAS
CSCD
北大核心
2021年第1期29-38,共10页
Advanced Engineering Sciences
基金
国家重点研发计划项目(2017YFC1502504)
国家自然科学基金重点项目(51639007)
四川省科技计划项目(2019YJ0145)。
关键词
山洪灾害
水沙耦合致灾
分区预警
预警指标
flash flood disaster
flood coupled sediment disaster
division warning
early warning index
