堰塞坝局部溃决输沙率试验研究

Experimental study of sediment transport rates by partly break of barrier dam

本文设计9组堰塞坝溃决的水槽试验,用摄影记录坝体变形的过程,通过录影数据分析,将坝体变形过程数值化,研究坝体级配、坝体内坡和初始溃口宽度对最大输沙率的影响。根据观察到的现象,可以总结以下规律:内坡坡度越大,最大输沙率越大,峰现时刻越早出现;拣选系数越大,最大输沙率先增大,随着粗沙继续增加,反而减小;初始溃口宽度越小,最大输沙率越大,峰现时刻越晚出现。

This paper is to study the scouring process of the barrier dam via nine series of dam break experiments.The sediment transport characteristics are studied with varied factors,such as the inner slope,θ,the non-uniformity coefficient,S and the width of the initial breach,b,adopting numerical body changing process.The results indicate that for a given S and b,with increasing angle of the inner slope,the peak sediment transport rate caused by the flow scour increased;for a given θ and b,with increasing non-uniformity coefficient,the peak sediment transport rate first increased,then reached the maximum,and finally decreased;for a given θ and S,with decreasing width of the initial breach,the peak sediment transport rate increased.