岩质滑坡?碎屑流的运动距离计算公式研究

滑坡?碎屑流的远程运动距离是碎屑流体所能够达到的最大堆积距离，是灾害预警和评估的重要指标。通过总结已有碎屑流运动距离研究成果，从岩体势能入手开展研究，并结合量纲分析，首先建立了运动距离与势能之间的基本方程。其后，采用4种颗粒材料开展岩质碎屑流滑槽试验，研究碎屑体体积V、滑移区坡度?、碎屑粒径d以及最大垂直运动距离H等对碎屑流运动距离L的影响，通过逐步拟合回归，建立了基于势能的岩质滑坡?碎屑流最大水平运动距离的计算公式。最后，采用汶川地震触发的38个岩质碎屑流以及17个其他典型岩质滑坡碎屑流数据对计算公式进行了验证，结果表明，考虑该运动距离计算公式具有较好的可靠性，能够为山区滑坡?碎屑流灾害预警工作提供理论指导。

Calculation model of the long-runout distance of rock avalanche

The long-runout distance of rock avalanches is the largest accumulation range that sediment can reach, which has great significance in disaster warning and risk assessment. This paper describes a calculation model to predict the long-runout distance, which is of interest in connection with the motion of landslide and mass movement. By summarizing the research results of long-runout distance of rock avalanches and basing on dimensional analysis, it is considered that the potential energy of rock mass plays an important role on long-runout, and that the long-runout distance (L) is the function of potential energy. Then, experiments were performed with 4 different quartz granular materials, and masses of these granular materials with various initial volumes were released from rest in a chute. The front position of avalanches was recorded. The effect of mass volume(V), the slope angle of transport zone(?), fragments particle size(d) and maximum vertical travel distance(H) on the long-runout distance(L) were studied. The calculation model for long-runout distance on potential energy was established by stepwise regression method. The data of 38 landslide-avalanches triggered by the Wenchuan earthquake and other 17 typical landslide rock avalanches that are widely used internationally were taken to verify the calculation model. The results show that the transport distance calculation model established by potential energy of rock mass is reliable and that the transport distance calculation model is suitable for rock avalanche disaster warning and risk assessment in mountainous areas.