水利学报2017，Vol.48Issue(7)：757-764,8.DOI:10.13243/j.cnki.slxb.20170109
非均质泥石流起动判别关系式
Distinguish relations for the critical intitiation of non-homogeneous debris flow
摘要
Abstract
As one of natural disasters,non-homogeneous debris flow is common in nature,occurring widely throughout the world in flood seasons especially in the southwest China.The formation mechanism of debris flow is highly concerned by scholars around the world.Studying the formation mechanism of debris flow and occurrence conditions is the basis for debris flow forecast and prevention.With 48 flume simulation experiments,the mechanism of debris flow and the quantitative relations of factors related to debris flow formation are revealed.According to sediment movement mechanics,Shields number is important to determine solid particle starting of debris flow.With the Shields number results classified by water quantity,vertical distribution of solid particle (non-homogeneous coefficient φ) and d50,the Shields number shows positive relations with particle median diameter d50 and water discharge Q with analysis.The vertical distribution of solid particle reflects the non-homogeneous properties and the starting order of particles.When particles at the upper layer are much coarser than those at the lower layer,the Shields number is the largest.In the aspect of the particle shear stress,the critical expression of particle starting(the ratio of water shear stress to critical particle starting stress,if the calculation value of the discriminant is larger than 1.0,then particles start.) are preliminarily established separately based on the overall fitting formula and break fitting formula of Shields starting drag curve.Through verification with the field data from Jiangjia Gully,the critical expression of the particle initiation based on the overall fitting formula has a smaller deviation,having the better applicability.These results above is very significant for both preventing and reducing debris flow disasters.关键词
非均质泥石流/起动过程/Shields数/起动判别关系式Key words
non-homogeneous debris flow/initiation processes/Shields number/critical expression of initiation分类
建筑与水利引用本文复制引用
舒安平,张欣,段国胜,王澍,师哲..非均质泥石流起动判别关系式[J].水利学报,2017,48(7):757-764,8.基金项目
国家自然科学基金项目(11372048) （11372048）
长江科学院开放研究基金项目(CKWV2015225/KY) （CKWV2015225/KY）
