结构面局部弱化影响下巷道围岩稳定性研究

Stability study of roadway surrounding rock under influence of local weakening of structural plane

为改善赋存结构面巷道围岩的支护效果,以巷道围岩结构面形成的局部弱化区力学特性为研究对象,通过试验确定结构面影响下的岩体试件强度、刚度及应力应变关系;并以实际巷道支护工程为依托,结合理论综合分析内外因共同作用下由结构面形成的局部弱化区对巷道岩体强度、刚度及应力应变关系的影响,提出巷道围岩局部弱化控制思路。结果表明：结构面形成的局部弱化区对岩体试件的强度、刚度和稳定性有控制作用,局部弱化区的位置和形态随试件内外因的变化而变化;围压对结构面倾角在45-60°之间的岩石试件强度和刚度弱化抑制效果更好,结构面倾角越接近60°,结构面形成的弱化区对岩体试件强度、刚度及稳定性的影响越大,巷道围岩的稳定性越差。

In order to improve the supporting effect of roadway surrounding rock in the occurrence structure,the mechanical characteristics of local weakening zone formed by structural plane of roadway surrounding rock were taken as an object of study. On the basis of experiments carried out by the authors,relationships between strength,rigidity and stress-strain were obtained under the influence of structural plane. Based on the data on a certain the actual roadway support project,the influences of the local weakening zone formed by the structural plane on the strength,stiffness and stress-strain relationships of roadway rock mass were comprehensively analyzed under the combined action internal and external effects with theory. A method was put forward for controlling local weakening zone of roadway surrounding rock.The result show that rock specimen strength,rigidity and stability are controlled by local weakening zone formed by structural plane,that the position and shape of local weakening zone change with the internal and external factors,that the effect of confining pressure is better for rock specimen strength and stiffness when the structral plane inclination between 45° to 60°,that the closer to 60 ° the angle is,the more greatly affected by the weakening zone,the strength,stiffness and stability will be,and the smaller the stability of surrounding rock will be.