基于三维地应力实测的巷道稳定性优化研究

Study on Drift Stability Optimization Based on 3D Geo-stress Measurement

地应力对巷道稳定性的影响是多方面的,断面形式和布置方式是影响巷道稳定性的决定因素。根据地应力分布特征,选取合理的巷道断面和布置方式是解决巷道变形与失稳问题的关键所在。研究采用目前技术上最先进的CSIRO套孔应力解除法分别对某矿地应力进行实测,分析总结了矿区的地应力分布规律。以此为基础应用三维数值模拟,设计不同方案研究巷道围岩应力和位移特征、塑性区分布情况,分别计算分析了不同走向巷道和不同断面巷道的稳定性状况。通过分析和对比,确定了维持巷道最小变形的优化设计方案:半圆拱或三心拱断面巷道稳定性优于梯形巷道,当走向与最大主应力方向平行时巷道稳定性最好。以研究结果为依据,建议矿山深部巷道采用拱形断面,布置在与最大水平主应力方向平行的岩层中,以减小地应力对巷道的不利影响,提高巷道的服务年限和使用效率。

Influence of geo-stress on the stability of the drift is in many aspects,roadway section and disposal mode are the most important factors affect the stability of the drift. Selecting appropriate roadway section and reasonable disposal mode is the key to solve problems of deformation and instability. According to distribution characteristics of geo-stress. the stress relief method by CSIRO overcoring was used to measure 3 D geo-stress in a mine. And regularities of distribution of geo-stress was brought to light by detailed analysis. Based on the foundation of understanding of 3 D geo-stress,three-dimensional model of drift was established to analyze drift stability. Kinds of schemes consist of different axial directions and different sections were used to discuss variation including stress,displacement and plastic zone distribution. By comparison and analysis of 3D numerical calculation,the optimum scheme is found that ensure the minimum deformation of drift. the stability of semi-circular arch section or threecentered arch section are superior to trapezoid cross section. When axial direction parallel with the maximum principal stress,influence of drift received is minimum. According to research result,we put forward some suggestions that arch section and parallel arrangement are favorable to reduce the disadvantageous effects of geo-stress,prolong the service life of the drift and enhance the use efficiency.