摘要
泥石流对不同岩性的敏感性存在明显差异,以中国泥石流最发育的小江流域为研究区,采集上、中、下游5个典型泥石流沟,9种类型岩石的19个风化物样品及5个泥石流堆积样品。通过塑、液限及渗透试验获取水理特征参数,选择与泥石流起动密切相关的塑限、塑性指数及渗透系数3个指标,并以欧式距离为基础来构建敏感性计算公式,对各指标进行敏感性综合分析。采用子流域泥石流敏感性统计分析法进行验证,研究结果表明,以风化物水理特征差异规律分析为基础的敏感性能较客观合理地刻画各岩性的敏感性规律,9种岩石的敏感性由小到大依次为:玄武岩、灰岩、白云岩、板岩、第四纪冲洪积、砂岩、粉砂岩、千枚岩以及泥岩。
The susceptibilities of debris flow to different rocks vary obviously; and the Xiaojiang River basin is taken as a case study to analyze the susceptibilities of debris flow to different rocks. Nineteen samples of weathering products of 9 kinds of rocks with different elevations and five samples of debris flow depositions are collected in five debris flow valleys in upper, middle and lower reaches of the Xiaojiang River basin. The hydrological characteristics of each sample are analyzed by liquid and plastic limits and permeation experiments. Three indices of hydrological characteristics, such as plastic limit Wp, plastic index Ip and permeability coefficient KT, are selected; and the Euclidean distance is employed to analyze the susceptibilities of debris flow to different rocks based on the hydrological characteristic analysis of the samples. According to the analytical results, the order of the susceptibilities of debris flow to these nine kinds of rocks in increasing sequence is as follows： basalt, argillaceous limestone, dolomite, slate, Quaternary deposit, sandstone, siltstone, phyllite and mudstone. In order to check this order, the susceptibilities of debris flow to rocks of various valleys in Xiaojiang River basin are calculated based on the results of susceptibility analysis. According to the susceptibilities of all valleys and distributions of debris flow valleys in Xiaojiang River basin, the susceptibilities of debris flow to different rocks are reasonable; and it may be helpful for the assessment of debris flow hazards and prediction of debris flow.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2008年第11期2227-2233,共7页
Chinese Journal of Rock Mechanics and Engineering
基金
中国科学院知识创新工程项目(KZCX3–SW–352)
公益性行业(气象)科研专项经费项目(GYHY200706037)
关键词
工程地质
泥石流
敏感性
水理特征
小江流域
engineering geology
debris flow
susceptibility
hydrological characteristics
Xiaojiang River basin
