RAMMS在泥石流运动模拟中的应用——以白沙沟泥石流为例

Application of RAMMS model on simulation of debris flow in the Basha Gully

以北川县坝底乡白沙沟泥石流为例,探讨RAMMS在泥石流模拟中的运用。2013年7月9日,强降雨引发的山洪携带大量碎块石及泥沙在白沙沟形成泥石流,在现场调查和泥石流形成机制综合分析的基础上,运用RAMMMS进行了数值模拟研究。研究表明白沙沟泥石流属暴雨沟谷型泥石流,沟域内相对高差大,地形陡峻,沟谷纵坡大,多迭水,短时集中降雨激发泥石流。根据现场调查所得数据和20年一遇泥石流流量,RAMMS数值模拟得出的最终冲出量为35 965.76 m^3,与雨洪法计算结果对比误差不超过6%,可信度较高。运用RAMMS可预测泥石流在不同洪水频率下的运动状况,对于研究白沙沟流域泥石流特征及其防治具有一定参考意义。

RAMMS model was used to simulate debris flow in Basha Gully in this paper. On July 9, 2013, flash flood induced by heavy rainfall caused serious debris flow and sediment transport in Baisha Gully. RAMMS model was used to conduct a numerical simulation study based on the field investigation and the comprehensive analysis of the basic characteristics and formation mechanism. Result shows that the debris flow in Baisha Gully is a type of debris flow with torrential rain, which is relatively high in the gully area with steep terrain. The slope of the gully is large with high drop flow in the gully. According to the data obtained from the field survey and with 20 years return debris flow, using RAMMS model for numerical simulation. The result show that the final rushing amount was 35,965.76 m^3. Compared with the calculation results of rain flood method, the error is not more than 6% , and the reliability is higher. The case study shows that RAMMS model can be used to analyze the movement status of different flood frequencies.