黄河茨哈峡桑吉沟泥石流灾害特征及防治措施研究

Study on the Disaster Characteristics and Prevention Measures of Sangjigou Debris Flow in Tshaxia of Yellow River

桑吉沟位于黄河茨哈峡水电站坝轴线上游470 m处,沟口为拟建混凝土砂砾石面板堆石坝趾板线,沟谷泥石流对电站建设期间的人员及设备安全构成威胁。通过现场调查研究,对桑吉沟泥石流的地质灾害特征、发生原因、规模、类型进行论述,并采用数量化综合评价方法对该泥石流沟的危险性进行评价,数量化综合判断结果表明,桑吉沟属中度危险泥石流沟。针对桑吉沟泥石流发育特征,建议采用以治为主、防为辅的防治原则,通过修建拦砂坝、谷坊坝及护坡,尽量减少物质来源进入沟谷,从而降低泥石流发生规模的作用。

Sangjigou is located at 470 m upstream of the dam axis of the Tshaxia Hydropower Station in the Yellow River.The gully mouth is the toe slab line of the proposed concrete sand gravel slab rockfill dam.The gully debris flow poses a threat to the safety of personnel and equipment during the construction of the power station.The geological disaster characteristics,causes,scale and types of debris flow in Sangjigou are discussed through field investigation and study,and the risk of the debris flow ditch is evaluated by quantitative comprehensive evaluation method.The results of quantitative comprehensive judgement show that Sangjigou is a moderately dangerous debris flow gully.According to the development characteristics of debris flow in Sangjigou,it is suggested to adopt the harnesses princple of prevention as the first and prevention as the second strategy.By building sand dam,Gufang dam and adopting slope protection,material souices can be reduced inflow into the valley as far as possible,so as to reduce the roce of debris flow occurrence scale.