黄土梁滑坡型泥石流2~#沟工程治理及效果评价

Engineering Measures and Their Effect for Mobilization of Debris Flow from Landslides at Huangliang 2~# Stream Vally

目前对谷坊、拦砂坝、排导槽等治理措施研究较多,但对滑坡型泥石流的治理研究较少。2008年9月24日,四川省北川县陈家坝乡黄土梁发生特大滑坡,诱发其下游的2~#沟发生特大泥石流,导致沟口103国道被掩埋,堵塞都坝河。为防止泥石流再次发生,对2~#沟泥石流进行了工程治理及治理效果评价。治理措施采用"2~#沟中游4座浅拦坝+2~#支沟中游3座浅拦坝+下游起点设置总长34.7 m束流堤,总长156.4 m排导槽,终点设置总长22.1 m导流堤,排导槽与103国道相交处,采用桥梁工程跨越排导槽",中游和下游统筹的治理方案,并分析了各分项治理工程的作用。与2008年9月24日暴雨相比,2013年8月7日和2016年7月21日2次强降雨活动未发生泥石流灾害,验证了黄土梁2~#沟泥石流防治工程效果较好,为类似滑坡型泥石流工程防治提供了参考。

Engineering measures such as dams, barrier dams, and guide grooves in certain catchments are studied extensively in China. However, few studies are reported on control measures mobilization of debris flow from landslides. An extremely large landslide occurred on September 24, 2008 in Huangtuliang of Beichuan County, Sichuan Province. This landslide caused a massive debris flow in the downstream 2~# ditches, burying the G103 national highway in the Mizoguchi,and blocking the Duba River. In order to prevent the debris flow from happening again, engineering measures and effects valuation were adopted in 2~# ditches. The control measures are four shallow bank dams in the midstream of 2~# ditch, three shallow bank dams in the middle of 2~# branch ditch, 34.7 m beam embankment at the downstream starting point, 156.4 m row of guide troughs, and 22.1 m diversion dike at the end point. The intersection of the trough and No.103 national highway is bridge construction across the guide troughs. The overall plan is made for the treatment of the middle and lower reaches of the river and the role of the various sub-projects is analysed. Finally, the prevention of debris flow disasters caused by two heavy rainfall events by the use of "2008-09-24" and "2013-08-07" and "2016-07-21" pverifies the better effect of the 2 nd gully debris flow control project of the Huangtuliang.This study provides reference for similar landslide debris flow engineering control.