九寨沟县勿角镇甲勿沟泥石流运动参数特征与堵河分析

ANALYSIS OF DEBRIS FLOW MOTION PARAMETERS CHARACTERISTICS AND RIVER BLOCKING OF JIAWU GULLY DEBRIS FLOW IN WUJIAO TOWN,JIUZHAIGOU COUNTY

甲勿沟于2020年8月17日凌晨发生大规模泥石流过程,泥石流对主河汤珠河造成严重堵塞,主河河水以及甲勿沟泥石流形成漫流之势,河水携带大量泥砂及碎石,淤埋了沟口下游的阳山村安置点以及勿角场镇。经过现场实地调查,测量多条泥石流过流断面,通过计算分析“8.17”泥石流的运动参数特征,“8.17”泥石流强度接近降雨强度为10 a一遇的泥石流强度,泥石流性质为稀性泥石流。甲勿沟泥石流松散固体物源丰富,容易造成主河道汤珠河堵塞,根据泥石流堵河判别公式计算,泥石流堵塞汤珠河的可能性较大。

In the early morning of August 17,2020,a massive debris flow occurred in Jiawu gully.Mudslides have severely blocked the Tangzhu River.The main river water and Jiawu gully debris flow formed the potential of overflow.The river carries a large amount of mud sand and gravel,silt buried in the gully mouth downstream of Yangshan village resettlement site and Wujiao town.After field investigation and measurement of multiple debris flow cross sections.The motion characteristic parameters of"8.17"debris flow are calculated and analyzed,the intensity of debris flow on"8.17"was close to the intensity of debris flow with rainfall intensity of once in lo years,the nature of debris flow is rare debris flow.Loose solids are abundant in Jiawu gully debris flow,easy to cause the main river Tangzhu blocked.Calculated according to the discriminant formula of debris flow blocking river,mudslides are likely to block the Tangzhu River.