深切河谷区河流陡峭指数与岩体质量的空间分布特征及其相关关系研究  

SPATIAL DISTRIBUTION CHARACTERISTICS AND CORRELATION BETWEEN CHANNEL STEEPNESS INDEX AND ROCK MASS QUALITY IN DEEP VALLEY AREA

作　　者：方文欣 王学良[2,3] 王俊飞 孙娟娟 祁生文 邓清海[1] 刘顺 FANG Wenxin;WANG Xueliang;WANG Junfei;SUN Juanjuan;QI Shengwen;DENG Qinghai;LIU Shun(Shandong University of Science and Technology,Qingdao 266590,China;Key Laboratory of Shale Gas and Geoengineering,Institute of Geology and Geophysics,Chinese Academy of Sciences,Beijing 100029,China;University of Chinese Academy of Sciences,Beijing 100049,China;Hebei University of Engineering,Handan 056038,China;North China Power Engineering Co.,Ltd.of China Power Engineering Consulting Group,Beijing 100120,China)

机构地区：[1]山东科技大学,青岛266590 [2]中国科学院地质与地球物理研究所,中国科学院页岩气与地质工程重点实验室,北京100029 [3]中国科学院大学,北京100049 [4]河北工程大学,邯郸056038 [5]中国电力工程顾问集团华北电力设计院有限公司,北京100120

出　　处：《工程地质学报》2022年第3期720-728,共9页Journal of Engineering Geology

基　　金：第二次青藏高原综合科学考察研究(资助号:2019QZKK0904);国家自然科学基金项目(资助号:42172304);云南省重大科技专项计划(资助号:202002AF080003)。

摘　　要：河流下切作用是深切河谷区地貌演化的重要地质营力。它常常通过对河道的下切和侧蚀过程等影响着河谷两侧斜坡的稳定性状态和斜坡演化。目前,在河流下切作用下斜坡岩体质量的空间分布特征及两者的定量化关系等方面研究较少。这在一定程度上制约着深切河谷区斜坡岩体稳定性预测及地质灾害易发性评价的发展。基于上述背景,本文依托青藏高原深切河谷区(澜沧江—金沙江)和G214左贡—虎跳峡段,基于岩体质量评价BQ系统和河流水力侵蚀模型,利用现场调查、统计和Matlab、Topotoolbox、ArcGIS、Origin等工具手段,研究了研究区河流陡峭指数(k_(sn))和岩体质量指标的空间分布特征、相关关系和内在机制。结果表明:在研究区,岩体质量与断裂密度、k_(sn)、工程岩组的皮尔逊相关性系数分别为:0.52、0.67、-0.11,即岩体质量与k_(sn)的相关性程度最高。基于横剖面形态提取和河谷边坡应力特征区分析发现:本文所研究岩体质量的特征分布区主要为对河流下切作用作出实时敏感响应的斜坡段,即河流下切作用的强烈影响段。基于研究结果,本文提出在深切河谷区,k_(sn)应该作为重要评价指标在表征河流下切作用对崩塌灾害易发性评价中进行考虑和使用。River incision is an important geological force for geomorphic evolution of deep valley.River incision and side erosion processes often influence the stability state and slope evolution of the slope on both sides of the valley.At present,little research results are available on the spatial distribution characteristics of slope rock mass and their quantitative relationship under the action of river incision.To some extent,this restricts the development of stability prediction of slope rock mass and susceptibility assessment of geological hazards in deep valley area.Based on the above background,this paper studies the spatial distribution characteristics of channel steepness index(k_(sn))and rock mass quality index in the study area.It uses on-site investigation,statistics,Matlab,Topotoolbox,ArcGIS,Origin and other tools and examines the BQ system of rock mass quality evaluation,the river hydraulic erosion model,the relavant relationships and internal mechanisms in the deep-cut valley area(Lancang-Jinsha River)and G214 Zuogong-Tiger Leaping Gorge section of the Qinghai-Tibet Plateau.The results show that the Pearson correlation coefficients of rock mass with fracture density,k_(sn)and engineering rock group are 0.52,0.67 and-0.11 respectively.The correlation degree between rock mass quality and k_(sn)is the highest.Based on the shape extraction of cross section and analysis of stress characteristic area of valley slope,it is found that the characteristic distribution area of rock mass studied in this paper is mainly the slope section which responds sensitively to river downcutting in real time,i.e.the section strongly affected by river incision.Based on the research results,this paper suggests that k_(sn)should be considered and used as an important evaluation index in evaluating the susceptibility of collapse disasters by characterizing river incision.

关 键 词：深切河谷区 归一化陡峭指数k 岩体质量评价BQ系统 G214 易发性评价指标 

分 类 号：TU452[建筑科学—岩土工程]