高山峡谷区域暴雨泥石流成灾临界阈值研究

项目名称： 高山峡谷区域暴雨泥石流成灾临界阈值研究

项目编号： No.41302224

项目类型： 青年科学基金项目

立项/批准年度： 2014

项目学科： 天文学、地球科学

项目作者： 于国强

作者单位： 西安地质矿产研究所

项目金额： 23万元

中文摘要： 深化区域暴雨泥石流临界阈值研究是山区泥石流预警预报研究的基础，也是减轻和防治泥石流灾害的难点和关键所在。本课题以舟曲3处典型泥石流沟为研究对象，从野外勘察、资料收集入手，通过原位测试、土工试验和数值模拟等方法，结合大量实时监测数据，定量阐明不同地质环境条件、不同下垫面情况下，泥石流在启动、运动过程中含水率的时空变化规律，揭示位移、流速、泥位和坝体应力对降雨的动态响应机制；进一步细化降雨特征指标，揭示不同地质环境条件下，激发区域暴雨泥石各降雨指标的函数关系，临界雨量（激发雨型、激发雨强）特征规律，确定激发泥石流启动的降雨临界阈值；分析泥石流启动的临界径流量、径流深，径流流速临界条件和水流含沙量对泥石流启动的影响，揭示不同下垫面情况下降雨转化为峰值流量规律、侵蚀产沙对泥石流启动的作用机制。为我国山区泥石流灾害防治奠定基础，为区域暴雨泥石流灾害调控决策、预警预报提供科学依据。

中文关键词： 舟曲；地质灾害；形成机理；临界阈值；预警判据

英文摘要： Enhancing the research on the critical threshold value of regional rainstorm-induced debris flows is the basis for studies on early-warning and forecasting of debris flows in mountainous areas, and the difficult point of and the key to mitigating and preventing debris flow disasters, too. With three typical debris flow ditch in Zhouqu as the subject of this study, and based on field survey and data collection, the experiments such as in-situ testing, geotechncial testing and numerical simulation and a large number of real-time monitoring data were done. Moisture content variation law of space and time were quantitatively analyzed in the process debris flow with various condition. The threshold values and critical initiation conditions of disaster-forming environmental factors of various kinds of debris flows in variable scales were elaborated, and a system of critical indexes was established for induction of debris flows by rainstorm in mountainous areas. The hydrodynamic conditions for debris flow occurring was studied in depth, the influential of the runoff and runoff depth and sediment on the process of debris flow were quantitatively analyzed, the TOPOFLOW model systematically reveal the runoff sediment effect on the debris flow initiation, formation and movement mechanisms on different underlying surface co

英文关键词： Zhouqu；geological hazard；formation mechanism；critical threshold；warning criterion