摘要
冰川终碛湖溃决泥石流是青藏高原常见的泥石流灾害类型之一,也是青藏高原地区泥石流防治的重点之一.在溃决洪水研究的基础上,结合泥石流本身的特征,针对瞬间部分溃决的情况,推导了冰川终碛湖溃决泥石流流量的计算方法.具体包括冰川终碛湖溃决口泥石流洪峰流量Qdmax=kQmax和距离溃决口一定距离的河道某处泥石流洪峰的最大高度Hd\%max=kHHmax.由于计算方法中涉及泥石流的特征参数,依据泥石流的特征,定义了特征参数的含义,并给出了计算方法k=1+(γd-γw)/(γ\%s-γd),kH=k·kG,kG是与沟道形态有关的参数.为了检验推导计算方法的合理性和精度,选定西藏米堆沟冰川终碛湖溃决泥石流作为实例,进行了验证.结果表明,推导计算方法的物理概念清晰,计算结果与实际调查数据在趋势上吻合.
Debris flow induced by glacier lake outburst is common in the Tibetan Plateau, which occurs abruptly and brings tremendous damages. Of special importance in the study are the discharge and its variation along the runway, including the most parameters for designing the measure against debris flow. This study presents a method for calculating the discharge, including the peak discharge at the outlet, Q~~d__(max)=kQ_(max), and the maximal height of the flow near the outlet, H~~d__(max)=k_HH_(max), where k_H=k\5k_G, k=1+(γ_d-γ_w)/(γ_s-γ_d), where γ_(d) is density of debris flow, γ_(w) is density of floodwater and γ_(s) is density of solid materials; and k_G is a coefficient concerning the gully form. The calculation of Q_(max) and H_(max) is induced by wave method under some hypotheses. In order to verify the validity of this calculation, a case study was carried out on the Midui Gully in Tibet Region. In stance, detailed calculation process of k and k_G has been provided. It is revealed that the calculation agrees well with the field investigation in general trend. Furthermore, comparison with other formulas is made and much improvement can be seen. Because the calculation of k_G has been simplified, it is not suited to use in other glacier lake outburst.
出处
《冰川冻土》
CSCD
北大核心
2004年第3期357-362,共6页
Journal of Glaciology and Geocryology
基金
国家自然科学基金西部重大项目(90202007)
中国科学院知识创新工程重大项目(KZCX2 306)资助
关键词
泥石流
洪峰流量
冰湖溃决
泥石流防治
debris flow
discharge
glacier lake outburst
measure against debris flow
