泥石流泥舌水力特性的沿程变化实验研究  

Experimental study on spatial hydraulic characteristics of debris flow jet

作　　者：郑志山 潘华利[1,2] 安笑 李炳志 杨奉广 ZHENG Zhishan;PAN Huali;AN Xiao;LI Bingzhi;YANG Fengguang(Institute of Mountain Hazards and Environment,CAS,Chengdu 610041,China;Key Laboratory of Mountain Hazards and Earth Surface Process,CAS,Chengdu 610041,China;University of Chinese Academy of Sciences,Beijing 100049,China;State Key Laboratory of Hydraulics and Mountain River Engineering,Chengdu 610041,China)

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,四川成都610041 [2]中国科学院山地灾害与地表过程重点实验室,四川成都610041 [3]中国科学院大学,北京100049 [4]水力学与山区河流开发保护国家重点实验室,四川成都610041

出　　处：《自然灾害学报》2019年第6期154-166,共13页Journal of Natural Disasters

基　　金：国家自然科学基金(41672318,51679229);水力学与山区河流开发保护国家重点实验室(四川大学)开放合作基金;中国科学院成都山地所135计划(135-1701);中国科学院青年创新促进会项目(2018405);云南省应用基础研究计划项目(2016FB074)~~

摘　　要：泥石流过坝泥舌的水力特性与拦砂坝下游冲刷坑的最终深度、长度和宽度等形态特征密切相关,准确认识泥舌下泄沿程上的水力特性对研究坝下游冲刷过程十分重要。通过进行6组泥石流容重条件、6组沟床纵坡条件泥舌下泄室内水槽实验,重点研究了泥舌在下泄沿程的运动轨迹、纵向厚度变化特征、横向宽度变化特征和下游入射角变化特征的水力特性,建立了泥舌水力特性与射距的关系,并通过分析泥舌水力特性与射距的相关关系得到泥石流容重、沟床纵坡对泥舌水力特性的影响。研究结果表明:(1)泥舌下泄运动类似于抛物体运动,在相同实验条件下,高容重泥石流和低沟床纵坡条件下对应的泥舌下泄运动轨迹曲线变化程度较大,低容重泥石流和高沟床纵坡条件下的泥舌下泄运动轨迹曲线变化程度较小;(2)泥舌纵向厚度随着射距的增大而增大,纵向厚度变化率与射距增大而增大并呈线性正相关性,二者线性斜率随着泥石流容重的增大先增大后减小、随着沟床纵坡的增大而减小;(3)泥舌横向宽度随着射距的增大而减小,横向宽度变化率随着射距的增大而减小并呈线性负相关性,二者线性斜率随着泥石流容重的增大而减小、随着沟床纵坡的增大先减小后增大;(4)泥舌下游入射角随着射距的增大而增大,下游入射角变化率随射距的增大而增大呈线性正相关,二者线性斜率随着泥石流容重的增大而增大、随着沟床纵坡的增大而减小。本研究着眼于泥舌下泄运动现象问题,研究了不同泥石流容重、沟床纵坡实验条件下泥舌在下泄沿程上的水力特性,以期准确认识泥舌水力特性,为研究坝下游防治冲刷提供参考。The hydraulic characteristics of debris flow jet through sabo dam were closely related to the downstream scour.It was very important to accurately understand the hydraulic characteristics of debris flow jet to study the downstream scour process.The indoor flume experiment under six groups of the density of debris flow conditions and six groups of the gully bed longitudinal slope conditions was carried out to study the characteristics of moving track,the longitudinal thickness variation,the width transverse and the downstream incident angle variation of debris flow jet.The relationship between hydraulic characteristics and experimental conditions was analyzed.The results showed that:(1)the movement of debris flow jet is similar to the motion of throwing objects.Under the same experimental conditions,the trajectory curve of the debris flow jet of high density or low gully bed longitudinal slope condition is larger than that of low density or high gully bed longitudinal slope conditions.(2)the longitudinal thickness of debris flow jet increases with the increase of ejection distance,and the variation rate of longitudinal thickness increases with the increase of ejection distance and presents a linear positive correlation.The linear slope of both increases firstly and then decreases with the increase of the density of debris flow.With the increase of the gully bed longitudinal slope condition,the linear slope decreases.(3)the width transverse of the debris flow jet decreases with the increase of the ejection distance,the change rate of the transverse width decreases with the increase of the distance,and the linear slope decreases with the increase of the density of debris flow.With the increase of the gully bed longitudinal slope condition,the linear slope first decreases and then increases.(4)the downstream incidence angle of the debris flow jet increases with the increase of the distance,and the change rate of the downstream incidence angle increases linearly with the increase of the distance.The linear slope incre

关 键 词：泥石流 拦砂坝 泥舌 水力特性 下游冲刷 实验研究 

分 类 号：TV144[水利工程—水力学及河流动力学] X43[环境科学与工程—灾害防治]