摘要
岩石在压缩加载过程中的变形由岩石母体的线弹性应变和微裂纹引起的非弹性应变组成,微裂纹扩展与裂纹尖端应力强度因子大小有着密切的关系.基于细观力学方法,分析了岩石微裂纹相对滑动的条件及扩展准则.运用RFPA2D程序,对在压缩条件下岩石单一微裂纹的扩展过程进行了数值模拟,结果表明,微裂纹在起裂扩展前,在相当一段时间内,原生裂纹上下2个裂纹面会发生相对摩擦滑动;岩石受压时微裂纹产生沿最大主压应力方向扩展的次拉伸裂纹,该次拉伸裂纹是岩石产生劈裂破坏的主要因素.
The deformation of rock,under compressive stress,is composed of the elastic strain and the inelastic strain caused by micro cracks.The expanding of cracks is tightly related to the strength factor of the crack tips.Based on micro mechanics method,this paper analyzes the expand and propagation criterion of the crack relative sliding in rock.The numerical analysis program RFPA2D is applied to simulate the micro-crack growth of rocks under compressive stress,and quantitative analysis is conducted on the evolution law of micro crack growth.It can be shown from the results that relative sliding occurs with friction between the crack surfaces in primary crack in a period time before the extension of micro cracks;Secondary tensile cracks that are along the maximum principle stress is caused when the rock is compressed,and the secondary tensile crack is the main factor causing the splitting failure of rocks.
出处
《矿业工程研究》
2011年第2期13-17,共5页
Mineral Engineering Research
基金
湖南省高校科技创新团队支持计划资助项目
关键词
细观力学
微裂纹
裂纹扩展
相对摩擦滑动
micro mechanics
micro-cracks
crack growth
relative sliding with friction