不同黏性均质土坝漫顶溃决破坏试验

Different viscous homogeneous earth dam overtopping failure test

为了探究坝体黏土含量、外坡比不同时的坝体漫顶破坏过程,进而分析坝体溃口演变机制。在控制上游流量恒定的条件下(0.2 L·s-1),分别进行了10种工况下的水槽试验,通过观察各工况下的试验过程,总结得出:坝体呈现2种破坏模式,剪切滑塌破坏和重力倾倒破坏;外坡比相同,随着坝体黏土含量的增加,坝体溃决以及洪峰到来所需要的时间也相对延长,在外坡比为1∶1以及1∶2时,坝体黏土含量为100%的洪峰流量到达时间分别为坝体黏土含量为0时的3.6和3.8倍;黏土含量相同,坡度越缓,坝体越不易遭到破坏,洪峰出现的时间也随之延后,在外坡比为1∶2时,坝体黏土含量为0和100%的洪峰流量到达时间分别是外坡比为1∶1的1.5和1.4倍。

In order to analyze the evolution mechanism of the dam breach,the dam overtopping failure process with different clay content and outer slope was studied. Keeping the upstream constant flow（0. 2 L · s^-1）,the flume experiments were performed under ten conditions,respectively. By observing the testing processes under different working conditions,the results showed that the dam has two failure modes∶ shear collapse failure and gravity toppling failure. Increasing of the clay content,the dam burst and the peak arrival time required was relatively prolonged with the same slope,the slope ratio was 1∶1 and 1∶2 the clay content of one hundred percent,time to peak were zero dam clay content of 3. 6 and 3. 8 times; When the clay content was same,the slope was slow,the less was easy to be damaged,the time of peak discharge has been delayed,in the slope of 1∶2 and the clay content of zero and one hundred percent,time to peak were slope ratio 1∶1 is 1. 5 and 1. 4 times.