泥石流输沙及其对山区河道的影响  

Debris Flow Sediment Transportation and Its Effects on Rivers in Mountain Area

作　　者：崔鹏[1] 何易平 陈杰[3] 

机构地区：[1]中国科学院水利部成都山地灾害与环境研究所 [2]College of Engineering San Diego State University,San Diego,CA 92182 USA [3]西南大学地理科学学院

出　　处：《山地学报》2006年第5期539-549,共11页Mountain Research

基　　金：国家杰出青年科学基金(40025103);国家自然科学基金重点项目(49831010)资助

摘　　要：泥石流能在很短时间内将大量大小混杂的固体物质输入主河,影响主河河床演变,形成灾害。在连续观测资料的基础上,对泥石流输沙的强度、级配和时空分布特征进行了分析。通过实际测量,分析了泥石流在沟道内冲淤特征以及影响泥石流冲淤特征的因素,如泥石流活动规模和局部沟道条件等。通过水槽实验,分析了泥石流与主河交汇的机理,将泥石流入汇主河的模式概括为掺混模式、潜入模式、推进模式和堵河模式,并且从能量角度阐释了汇流区的水沙交汇特征,提出了泥石流堵江的判据。最后,分析了泥石流多发区受泥石流入汇影响,主河河床在平面形态、横断面形态、纵断面形态和河型等方面的变化特征。Debris flow, mixing big solid matter with small ones, may transport large quantity of sediment into fiver in very short time, which consequently affect riverbed evolution and cause disasters. Firstly, the characteristics of debris-flow sediment transportation such as intensity, granule gradation and space-time variation were discussed on the base of continuous observation data. Then, the scouring and silting characteristics of debris flow and their affecting factors including debris flow scale and local channel condition were explored by analyzing field survey data. In addition, through flume experiments, the mechanism of debris flow interacting on main fiver was studied. And patterns of debris flow interjecting in the main river were generalized as debris flow mixing up with water in main river, debris flow diving in the water of main river, debris flow advancing straightly with the approximate same flow level of the main river, and debris flow blocking up main channel. Moreover, the movement characteristics of debris flow and sediment in confluence were expounded in terms of energy, and the criterion of debris flow clogging river was put forward. At last, the evolution of riverbed in planar shape, transect, longitudinal section and river pattern influenced by debris flow were discussed.

关 键 词：泥石流 输沙 冲淤 交汇 河床演变 

分 类 号：P642.23[天文地球—工程地质学]