基于斜坡失稳破坏模式的软弱变质岩区岩质滑坡易发性评价  

Evaluation of Susceptibility to Rocky Landslide in Soft Metamorphic Rock Area Based on Failure Mode of Slope Instability

作　　者：李金洋 佘涛[1,2] 陈欢[1,2] 孙金辉[1,2] 赵重[1,2] LI Jin-yang;SHE Tao;CHEN Huan;SUN Jin hui;ZHAO Zhong(Institute of Exploration Technology,CAGS,Chengdu Sichuan 611734,China;Technical Center for Geological Hazard Prevention and Control,CGS,Chengdu Sichuan 611734,China)

机构地区：[1]中国地质科学院探矿工艺研究所,四川成都611734 [2]中国地质调查局地质灾害防治技术中心,四川成都611734

出　　处：《探矿工程（岩土钻掘工程）》2018年第8期83-87,共5页Exploration Engineering:Rock & Soil Drilling and Tunneling

基　　金：中国地质调查局地质调查项目"涪江流域1:5万环境地质调查"(编号:DD20160251)

摘　　要：滑坡受控于地质环境条件和坡体地质结构,不同地质结构的斜坡失稳破坏的模式存在差异,本文以后龙门山千枚岩区为例,基于现场调查,梳理总结了区内岩质滑坡发生的力学模式与斜坡地质环境、坡体结构之间的关系,进而选取控制滑坡发生的关键因素,运用ARCGIS软件的加权叠加功能定量划分了不同模式滑坡的易发区域,主要取得以下认识:(1)滑移-拉裂式滑坡主要发生在坡度30°~45°的顺向飘倾坡内、滑移-溃曲式滑坡发生在坡度30°~45°的顺向伏倾坡内、倾倒变形主要发生在岩层倾角>65°的反向斜坡内;(2)区内倾倒变形易发区面积为8.73km2、滑移拉裂易发区面积为4.31km^2、滑移溃曲易发区面积为3.28km^2,以倾倒变形类型的滑坡为主,已发生滑坡与易发分区结果比对证明了滑坡易发分区与实际情况基本吻合。The landslide is controlled by the geological environment conditions and the geological structure of the slope. There are differences in the pattern of slope instability of different geological structures. Take Houlongmenshan phyllite rock area as an example, based on the field investigation, the relationship between the mechanical model of the rocky landslides in this area ＆ the slope geological environment and the slope structure is summarized, and then select key factors which control the occurrence of landslides, such as slope structure, slope gradient, and slope surface morphology, etc., and use the weighted stack function of ARCGIS software to quantitatively classify the landslide-prone areas of different models. The main understanding are achieved. （1）The phyllite is a layered soft rock. There are 3 types of landslide： ＂the sliding-tension cracking model＂, ＂the creep-bending model＂ and ＂scale toppling model＂. ＂The sliding-tension cracking model＂ mainly occurs at a slope of 30°~ 45° where rock dip more than slope. ＂the creep-bending model＂ occurs within the slope of 30°~45° where rock dip less than slope, and ＂the scale toppling model＂ occurs in the reverse slope where the rock dip is more than 65°. （2）The overlay analysis based on ARCGIS software showed that： the area of ＂the scale toppling model＂ area in the zone is 8.73km^2 , the area of ＂sliding-tension cracking＂ area is 4.31km^2 , the area of ＂the creep-bending model＂ area is 3.28km^2 , and the landslide type is dumped. The result of the comparison of landslides and areas with high incidence of landslides has proved that the landslide-prone areas basically agree with the actual conditions.

关 键 词：斜坡结构 变质岩 滑坡 易发性 

分 类 号：P642.22[天文地球—工程地质学]