滑坡堰塞湖溃坝波影响因素分析

滑坡堰塞湖坝体随着上游水位的不断上升极易失稳。基于流体计算软件Fluent,对水体在重力作用下的塌落及演进过程进行数值模拟,分析溃坝洪水在下游河道传播过程中的影响因素,结果表明:上下游水深比、下游河道坡降及弯曲程度均对溃坝洪水的推进速度、波形及流量产生影响。水深比比较小时,下游洪水推进较快;下游河道坡降越大,洪水推进速度越快,流量越大;下游河道弯曲度≥0.25时,溃坝洪水受影响比较明显,波前传播速度减缓,能量耗散增大。

Analysis on Influential Factors of Lake Water Down-Stream Flooding Due to Sudden Breakage of Landslide Dam

Along the rising water lever of upstream,the barrier lake dam is easy to become instability.To study the dam break flow’s influencing factors in transmission of downstream channel,a numerical simulation of the water’s action which was in the gravity of the collapsing and evolution process was done with a fluid calculation software Fluent.The results show that there are three factors affecting to advancing speed,wave and flux of dam-break flood,which are water depth scale of upstream and downstream,rail slope ratio of downstream channel and bending degree of channel.Furthermore,a littler value of water depth scale,faster floods of downstream advances.If the rail slope ratio gets bigger,the velocity and flux of flood become larger.And when bending degree’s value gets more than 0.25,dam-break flood is affected quite obviously.At this moment,velocity of wave front reduces and energy dissipation increases.