云南东川区烧房沟“7·31”弃渣型泥石流成灾机理

2008年7月31日晚持续强降雨导致云南省东川区舍块乡烧房沟爆发泥石流灾害,造成了人员伤亡、公路、民房以及大量公共基础设施受损。这次泥石流发生在地质环境较为脆弱的工矿区,该泥石流的爆发是弃渣的不合理堆放与强降雨共同作用的结果。通过现场实地调查与试验等方法,分析了泥石流形成的降雨条件、地形条件、物源条件,研究了烧房沟泥石流启动、流通以及堆积过程。研究结果表明:集中的松散弃渣物源以及强降雨是烧房沟发生泥石流的主要原因。从发展趋势上看,烧房沟泥石流处于发展期,仍存在爆发泥石流的可能性。根据泥石流特征提出如下治理措施:拦、护为主,结合潜坝消能;及时清淤,恢复植被;实时监测,临灾预警。

Hazard mechanism analysis of Shaofang ditch waste slag debris flow in Yunnan Dongchuan district on July 31th

The continuous heavy rainfall in the evening of 31 July 2008 led to the outbreak of Shaofang ditch debris flow in Yun‐nan Dong chuan Shekuai district ,and it caused casualties and damage to roads ,houses and a number of public infrastructure .The debris flow occurred in the geological environment of vulnerable mining areas ,and the outbreak of debris flow was the result of interaction between unreasonable spoil pile and heavy rainfall .The rainfall conditions ,terrain conditions and source conditions of debris flow were analyzed ,and the starting ,circulation and accumulation process of the debris flow in the Shaofang ditch were studied by field survey and test methods .The research results showed that :the loose residue source and strong rainfall were the main reasons for the occurrence of debris flow of Shaofang Ditch .Judging from the trend ,the Shaofang ditch debris flow was at the stage of development ,and the possibility of the outbreak of debris flow still existed .According to the characteristics of deb‐ris flow ,the following measures were put forward ,and these measures were stopping and supporting ,combined with dam energy dissipation ,vegetation restoration ,timely dredging ,real‐time monitoring ,and disaster early‐warning .