川藏公路然乌-鲁朗段泥石流灾害成因分析及定量化分区

CAUSE ANALYSIS AND QUANTITATIVE ZONATION OF MUDFLOW HAZARDS ALONG THE RAWU-LUNANG SECTION,SICHUAN-TIBET HIGHWAY

独特的地质、地形地貌、水文以及气候条件使得川藏公路然乌至鲁朗段各种山地灾害极其发育,尤其以泥石流灾害最为严重。根据前人的成果以及作者的实地调查,认为复杂的地质构造、强烈的地壳运动和河流切割、频繁的地震、丰富的松散堆积物、有利的地形地貌、现代冰川以及丰沛的降雨是研究区泥石流灾害频繁发生的主要原因。为了更有效地进行减灾防灾,采用岩石工程系统方法对研究区对泥石流进行了定量化分区。通过与初步定性泥石流分区以及泥石流灾害的分布情况进行对照,验证了定量泥石流分区的正确性和可行性。

Unique geological, geomorphic, hydrological and climatic conditions cause various kinds of mountainous hazards, especially very serious mudflow hazards, to occur frequently in the Rawu-Lunang section, Sichuan-Tibet Highway. On the basis of previous research and the authors＇ field investigations, it is thought that the complex geological structures, strong crust movements and rivers erosions, frequent earthquakes, abundant loose deposits, favorable geomorphology, well-developed modem glaciers and plentiful precipitation are the principal causes of triggering frequent mudflows in the study area. For the purpose of more effective disaster prevention and reduction, the rock engineering system （RES） method is adopted to make a quantitative zonation of mudflows in the study area. By comparing the quantitative mudflow zonation with the preliminary qualitative zonation and distribution of mudflows, it is verified that the quantitative mudflow zonation method is correct and feasible.