泥石流启动临界土体含水量及其预警应用  

Critical Soil Moisture for Debris Flow Initiation and Its Application in Forecasting

作　　者：胡凯衡[1,2] 马超[1,2,3] 

机构地区：[1]中国科学院山地灾害与地表过程重点实验室,四川成都610041 [2]中国科学院水利部成都山地灾害与环境研究所,四川成都610041 [3]中国科学院大学,北京100049

出　　处：《地球科学与环境学报》2014年第2期73-80,共8页Journal of Earth Sciences and Environment

基　　金：中国科学院重点部署项目(KZZD-EW-05-01);国家自然科学基金重点项目(41030742);中国科学院水利部成都山地灾害与环境研究所青年百人团队项目(110900K235)

摘　　要：传统的泥石流预警方法多基于前期和实时降雨量等间接指标,但实际上直接影响泥石流启动的关键物理参数是土体含水量,通过分析土体含水量的变化来判断泥石流启动更为直接可靠。首先定义了泥石流启动的临界土体含水量的概念,然后基于国内外泥石流启动的观测试验数据,采用逐步回归分析方法,建立了临界土体含水量与土体渗透系数、孔隙度和颗粒曲率系数的经验关系,进而提出一种基于临界土体含水量和实时降雨的泥石流预警方法。最后,以云南东川蒋家沟1999年7月16日发生的一场泥石流为实例进行演算和验证。结果表明:该方法在可靠性和准确性上优于传统利用临界线和暴发线判别泥石流的预测模型。Most of traditional debris flow forecasting methods are based on indirect variables such as antecedent and real-time rainfalls.But the key factor influencing directly the debris flow initiation is soil moisture,which is more reliable for debris flow forecasting.Firstly,the concept of critical soil moisture for debris flow initiation was defined;secondly,based on the experimental and observation data of debris flow initiation at home and abroad,the empirical relationships between critical soil moisture and permeability coefficient,porosity,coefficient of paritcle curvature were obtained by the means of step-wise regression analysis;finally,the forcasting method for debris flow based on critical soil moisture and real-time rainfall was proposed.The method was tested and verified by the debris flow happened at Jiangjiagou of Dongchuan,Yunnan on 16July,1999.The results show that the reliability and accuracy of new forcasting method is better than the traditional forecast method for debris flow based on critical line and occurrence line.

关 键 词：泥石流 预警 临界土体含水量 孔隙度 渗透系数 曲率系数 降雨 

分 类 号：P642.23[天文地球—工程地质学]