高陡边坡深部破裂岩体的变形模式及成因分析

Deformation Pattern and Cause Analysis of the Deep Crack in High and Steep Slope

研究目的:高陡岩质边坡的稳定性评价问题是工程建设中的重大工程问题。通过研究高陡边坡深部破裂发育特征、地球化学特征、变形破坏模式、破坏类型、地质特征、控制因素及成因分析,可进一步为西南高陡边坡深部破裂岩体结构、岩体质量及边坡稳定性研究奠定基础。本文通过现场调查、平硐岩体结构统计等方法,揭示高陡边坡深部破裂的破坏类型及发育特征,并通过对研究区岩性条件、岩体结构、地应力、微地貌及河谷演化等控制因素的分析,对深部破裂的成因进行探讨。研究结论:(1)金沙江上游高边坡特殊的岩性、高地应力、强烈构造运动等地质条件,造成了高陡岩质边坡深部变形破坏形式复杂和多样,根据深部变形破坏的特征可划分为:剪-张性、压-剪性和张性深部破裂;(2)构造运动、河谷演化、高地应力重分布等区域因素与地质特征、高陡边坡形态等为深部破裂形成和发育特征的成因机制;(3)本研究成果可为高陡边坡勘察、稳定性评价等方面提供工程地质依据。

Research purposes: The stability evaluation of high and steep slope has become a major engineering problem in the construction projects. By studying the development characteristics,geochemical characteristics,deformation and failure pattern,failure types,geological characteristic,controlling factors and cause analysis of the deep cracks of the high and steep slope,the special geological phenomenon is analyzed to provide a scientific basis for a comprehensive analysis on rock mass structure,rock mass quality,and slope stability in southwest China. In this paper,the failure types and development characteristics of deep crack of high and steep slope are revealed by the method of field investigation and structural statistics of rock mass,and the causes of deep crack are discussed through the analysis of controlling factors such as lithology,rock structure,geostress,micro landform and river valley evolution.Research conclusions:( 1) The special lithology,high geostress,strong tectonic movement and other geological conditions of the high slope in the upper reaches of Jinsha River have resulted in complexity and diversity. Based on the characteristics of deep deformation and failure,it can be divided into three categories: cut-shear crack,compressive shear crack and tensioning deep crack.( 2) Regional factors such as tectonic movement,river valley evolution,and redistribution of high geostress,geological characteristics and slope shape are the cause mechanisms for the formation and development of deep cracks rock structure.( 3) The research results can provide engineering geological basis for high and steep slope investigation and stability evaluation.