新疆伊宁克孜勒赛黄土滑坡堵溃型泥石流成灾模式

Kezilesai loess landslide dam-breaking debris flow hazards model in Yining County,Xinjiang

2017年4月2日凌晨,新疆伊宁县喀拉亚尕奇乡境内由于持续降雨,诱发黄土滑坡堵溃型泥石流灾害,造成直接经济损失50余万元。本文在查明滑坡堵溃型泥石流形成条件、成灾模式基础上,分析了克孜勒赛沟泥石流静力学和运动特征,得出如下结论:(1)此次滑坡堵溃型泥石流成灾模式为:持续降雨→黄土斜坡变形破坏→滑坡滑入沟道形成堰塞坝→堰塞坝溃决形成泥石流;(2) 3#、4#、5#、6#和7#滑坡堰塞坝溃决洪峰流量分别为5. 4 m3/s、10. 1 m3/s、49. 5 m3/s和30. 3 m3/s;(3)泥石流断面流速为1. 88～3. 50 m/s,断面流量为4. 51～41. 39 m3/s,泥石流堆积扇最大长度263. 1m,最大宽度212. 6 m。调查研究结论对克孜勒赛沟滑坡堵溃型泥石流的防治具有现实意义,并提出了针对性的防灾减灾建议。

At 0:10 on April 2nd,2017,a sustained rainfall induced landslide-debris flow disasters in Kalayagaqi Town of Yining County,Xinjiang,causing a direct economic loss of more than 500 thousand yuan. Based on the landslide-debris flow formation conditions,the author analyzes the static and dynamic characteristics of the Kezilesai Gully debris flow.The results show that the formation of landslide-debris flow was stimulated by the successive rainfall,loess landslide,landslide dam,landslide dam breaking and then debris flow.The No.3&4、No.5,No.6and No.7loess landslide dam with a peak rate of 5.4m^3/s、 10.1m^3/s、49.5m^3/s and 30.3m^3/s.The debris flow velocity varied from 1.88m/s to 3.50m/s,and discharge of debris flow varied from 4.51m^3/s to 41.39m^3/s.The maximum length of debris flow accumulated fan was 263.1m,with the maximum width 212.6m.The investigation conclusion has practical significance to prevention and control of Kezilesai landslide-debris flow,and put forward the correspondingsuggestions on disaster prevention and mitigation.