冰湖溃决泥石流形成的临界条件

随着全球气候的变暖, 在世界上许多高山峡谷区的冰湖溃决及其溃决洪水引发的泥石流, 经常对下游居民及其他基础设施造成极为严重的危害. 使用水槽试验的方法, 从单宽流量和库容、沟道纵坡、堆积物粒径3个方面探讨了冰湖溃决泥石流形成的影响因素和临界条件. 结果显示: 冰湖溃决泥石流形成与否不仅与溃决洪水提供的能量有关, 还与参与泥石流活动的沟床物质特性紧密相关. 通过对试验数据的分析, 当泥石流形成的特征参数K>2.66时, 冰湖溃决洪水可以演化为泥石流. 该种方法可以对危险性冰湖的预测提供理论参考.

The critical condition for the formation of debris flow induced by glacial lake outburst flood

Along with the glacier retreating due to global warming, many cases of glacier lakes outburst and consequent debris flows occurred in alpine areas, which typically resulted in great harms to inhabitant and other downstream infrastructures. Base on flume tests, considering the different combination of unit discharge, reservoir capacity and sediment grain size, the formation of critical conditions and influential factors of debris flow due to glacier lake outburst floods (GLOFs) were studied herein. It is found that whether debris flows be formed or not depend on the capacity of GLOFs and the features of materials in the channel. Analyzing the data obtained from the flume tests reveals that the GLOFs could evolve to debris flow when the parameter K>2.66. The method presented herein could provide theoretical foundation for risk assessment of dangerous glacier lake.