中巴经济走廊泥石流活动性分析——以中巴公路奥布段为例

Analysis of debris flow damage along the China-Pakistan Economic Corridor:taking Aoyitake-Bulunkou Section of the Sino-Pakistan Highway as a case

中巴经济走廊内的中巴公路奥布段泥石流频发且类型复杂,严重影响着安全出行和贸易流通。在对中巴公路奥布段沿线泥石流沟谷纵剖面形态分析的基础上,揭示其形态指数特征和活动程度,并从区域地形、地质和气象等因素方面探讨泥石流的活动性差异成因及危害性。研究发现:公路沿线泥石流类型主要包括冰川型和降雨型两种,冰川型泥石流为27条,降雨型为26条。冰川型泥石流活动性强烈,形态指数N≥1的沟谷占冰川型沟谷总数的81%,多数沟谷形态呈下凹状;降雨型泥石流活动性相对较弱,形态指数N≥1的沟谷占其总数的50%,沟谷形态多呈上凸状。研究区大落差地形、不同物源供给和充沛水源条件等对泥石流的发育和活动具有重要影响,也是不同类型泥石流活动性差异的控制因素。研究结果可为研究区泥石流预测和防治提供指导,也可为中巴经济走廊区内交通工程选线和泥石流防治提供参考。

Debris flow s along the Sino-Pakistan Highw ay have developed with various types and seriously affected the tourism and trade through the China-Pakistan Economic Corridor. Based on morphological features of debris flow gully profiles along the highw ay,in this paper,the morphological characteristics and activity level of debris flow s has been revealed,the causes and hazards of debris flow s have been discussed from regional geology,topography,meteorological factors and so on. It is found that the major types of debris flow along AoyitakeBulunkou Section of the Sino-Pakistan Highw ay can be divided into rainfall type（ 26 gullies） and glacial type（ 27 gullies）. Glacial type debris flow has powerful activity,i. e.,the ratio of glacial debris flow shape index N≥1 accounting for 81% of the total glacier gullies,and most of them being concave parabolas; rainfall type debris flow has less activity,i. e.,the ratio of rainfall debris flow shape index N≥1 accounting for 50% of the total glacier gullies,and most gullies shapes being convex parabolas. A large fall,rich material supply and plenty of water supply have significant influence on the development and activity of debris flow s and they are also controlling factors for the difference in activity among various types of debris flow s. The research results w ould be useful for debris flow forecast and control along the highw ay in the China-Pakistan Economic Corridor and be helpful for traffic engineering route selection and debris flow control.