窗口坝拦截泥石流性能试验研究

泥石流窗口坝是一种常见的泥石流防治工程措施,具有拦砂节流、护床固坡等重要调节功能。为了探寻泥石流的过坝特征,通过室内模拟试验,运用控制变量的方法对不同类型泥石流的过坝情况进行了探讨。试验发现,泥石流过坝前后颗粒组成的变化与泥石流密度相关性较大,在泥石流密度为1 650 kg/m³时,窗口坝对泥石流的筛选能力最强;泥石流过坝后密度降低情况较明显,并且受泥石流窗口坝闭塞类型的影响,不同闭塞类型下泥石流密度降低率具有相似规律,在泥石流密度为1 800 kg/m³左右时,泥石流密度降低率最大;通过回归分析得到了拦排比L与泥石流密度γ_c的关系式。

Experimental Study on Performance of Window-Frame Dam Intercepting Debris Flow

As a common measure of preventing debris flows,window-frame dam has functions of intercepting sedi-ment and protecting riverbed and slopes.Through indoor simulation,the characteristics of debris flows passing through window dam was researched by controlling different variables.Results reveal that the variation of particle composition of debris flows before and after passing through the dam is largely correlated with the density of debris flow.When the density of debris flow is 1 650 kg/m3 ,the window dam’s sediment interception capacity is the lar-gest.The density of debris flow decreases remarkably after passing through the window dam,and the decrease is af-fected by the type of window dam blocking;the regularity of decrease is similar despite different blocking types;when the density is around 1 800 kg/m3 ,its decrease is the largest.By regression analysis the relation between sediment interception ratio L and debris flow density γc was also obtained.