新藏公路新疆段泥石流灾害初探

新藏公路新疆段沿线共有泥石流灾害149处，直接危害线路53．05km。泥石流可分为暴雨型、冰雪融水型及雨水和冰雪融水混合型三个成因类型．其灾害集中分布于哈拉斯坦河、采拉克河、叶尔羌河及喀拉喀什河沿溪线路段。沿线泥石流具有松散堆积物丰富，水源不足，暴发频率低，规模火，受冰川和气候变化影响大等特点。在对泥石流成灾方式、活动现状和发展趋势分析研究的基础上．提出了灾害治理的基本原则和拟采取的主要工程措施及进一步工作的建议。

An Approach on Debris Flow Hazards Along the Xinjiang-Tibetan Highway Line in Xinjiang

The Xinjiang Tibetan Highway line stretches over Tarim Basin and Kunlun Mountains with length of 654.5km in Xinjiang, which is one of the most important key national traffic lines to the western boundary of China. Along the highway line, geological tectonics are complex, Neo tectonic movement and seismic activity is quite extensive, glaciers and accumulated snow distribute broadly and rainstorm break out frequently, thus induce a great number of debris flows in Hanasitan River, Sailake River, Yarkant River and KaraKashi River valley. It is investigated that there are 149 debris flows along the highway line, among which 129 belong gully type and 20 belong to slope type; 53.05km long highway line is threatened by debris flow hazards. Debris flows are triggered by rainstorm, melt water of glaciers and accumulated snow or both of them. Debris flow fluid is major in sub viscous and rock water flow type due to shortage of fine granular in solid materials, which break out once in several or dozen years,with large scale and easily influenced by climate fluctuation and glacier changes. Debris flows often deposit and bury road surface, block bridges and culverts, erode and destroy roadbed and basement of bridges and culverts, and block transportation. With the global climate change and intensive seismic activities, debris flow will become more extensive and generate serious damages to the highway in near future. According to the active features and damage forms of debris flow on highway engineering, a series of disaster controlling principles and suggestions in the next step are put forward. The main mitigation measures in future highway construction are suggested , which are concrete road surface, bridge and culvert over crossing works, gully bed anti eroded works, blocked dams, drainage engineering and debris silting field et al.