平武县鱼池沟泥石流特征及治理措施研究

Research on the characteristics and treatment measures of the Yuchi Gully debris flow in Pingwu County

摘要:

“5.12”汶川特大地震产生了大量泥石流灾害，造成了重大的人员伤亡和经济损失。震后几年，经历数个雨季，灾区的泥石流灾害仍然很多。本文以平武县鱼池沟泥石流为例，对山区暴雨沟谷型泥石流的形成条件、基本特征以及治理措施进行研究。鱼池沟泥石流属于黏性泥石流，容重为1.62 t/m³，采用雨洪法，计算求得泥石流沟口20年一遇的峰值流量为53.48 m³/s，一次性泥石流过流总量为2.54万m³，一次性泥石流固体物质冲出量为1.05万m³，为泥石流的治理工程提供了设计参数。在此基础上提出“潜槛群+缝隙坝+排导槽+盖板涵+路面恢复”的治理措施，治理效果良好。对于类似的暴雨沟谷型泥石流，特别是沟谷纵坡降大、沟道狭窄、没有库容空间的泥石流沟的治理工程设计具有一定的参考价值。

Abstract:

The Wenchuan Earthquake on May 12th， 2008， triggered a large number of debris flow disasters， resulting in a significant number of casualties and huge economic losses. In the years following the earthquake， debris flow disasters in the disaster-stricken areas continued to occur frequently after several rainy seasons. This paper takes the debris flow in Yuchi Gully in Pingwu County as an example to study the formation conditions， basic characteristics， and control measures of mountain rainstorm-induced gully-type debris flows. The debris flow in Yuchi Gully is a viscous debris flow with a bulk density of 1.62 t/m3. Using the rainstorm-flood method， the peak flow rate at the gully mouth of the debris flow with a recurrence interval of 20 years is calculated to be 53.48 m3/s. The total volume of a single debris flow passing through is 25400 m3， and the solid material discharge of a single debris flow is 10500 m3. These data provide design parameters for the debris flow control project. Based on these data， a comprehensive control measure of “submerged sill group+slit dam+diversion channel+covered culvert+road surface restoration” is proposed， and it has achieved good control results. This measure has certain reference value for the design of control projects for similar rainstorm-induced gully-type debris flows， especially those with large longitudinal gradients， narrow channels， and no reservoir storage space.