基于流深和弯道超高的泥石流淤积范围划分  

Delineation of Debris Flow Inundation Range Based on Flow Depth and Curve Superelevation

作　　者：刘清华 唐川[2] 余斌[2] LIU Qinghua;TANG Chuan;YU Bin(College of Environment and Ecology,Chengdu University of Technology,Chengdu 610059,China;State Key Laboratory of Geohazard Prevention and Geoenvironment Protection,Chengdu 610059,China)

机构地区：[1]成都理工大学环境学院,成都610059 [2]地质灾害防治与地质环境保护国家重点实验室(成都理工大学),成都610059

出　　处：《山地学报》2018年第4期581-588,共8页Mountain Research

基　　金：国家自然科学基金项目(41402316);四川省国土资源厅科学研究计划项目(KJ-2016-09)~~

摘　　要：针对缺乏大比例尺地形图和历史灾害资料记录的地区,提出一种沟谷型泥石流淤积范围划分新方法。方法假定峰值流量时泥石流形成最大淤积范围,泥石流纵向淤积远端为堆积扇前缘。泥石流沟口过流断面最大平均流深(h0)被假定为堆积扇上其他过流断面的特定流深,h_0由峰值流量和沟口断面参数估算得到。利用堆积扇地形图,在相邻两条等高线间获得由h0确定的泥石流特征过流断面的位置和宽度,并对弯道处的特征过流断面宽度进行弯道超高修正。根据堆积扇上特征过流断面的分布确定泥石流淤积范围。3条泥石流案例用于方法验证,结果表明方法划定的淤积范围与实际淤积范围较一致,堆积扇上房屋的阻挡和局部相对平坦的地形是误差产生的主要原因。该方法具有操作简单、快速、客观、可重复的特点。A new method for delineating the inundation range of a confined debris flow was proposed in this research,which could deal with debris flow occurrences lacking large-scale topographic maps and historical disaster data.The method assumed that debris flows bring about the maximum inundation ranges at the peak discharge,and the end of longitudinal deposition of a debris flow is the front edge of a debris flow fan.The maximum average flow depth(h 0)of a cross-section at gully month was assumed to be applicable to all of cross sections on debris flow fan,and h 0 could be estimated in terms of peak flow value and geometric parameters of a cross-section at gully mouth.The position and width of a characteristic debris flow cross-section defined by h 0 were obtained between adjacent two contour lines in topographic map,and the width had to make further curve superelevation correction.The inundation range of a debris flow can be determined according to the distribution of the characteristic cross sections on alluvial fan.Three cases of debris flows were used for method verification.The results showed that the inundation ranges delineated by our proposed method were generally consistent with field observations,although blockage of houses built on the fans as well as the relatively flat topography mainly resulted in minor errors.The method is simple,fast,objective and repeatable to use.

关 键 词：堆积扇 淤积范围 泥石流峰值流量 过流断面流深 淤积宽度 弯道超高 

分 类 号：P642.23[天文地球—工程地质学]