巷道尺寸及布置对围岩稳定性的影响分析

Impact Analysis of Roadway Size and Layout on Stability of Surrounding Rock

为了分析巷道尺寸及布置对围岩应力、塑性区及变形特征的影响,采用理论分析及数值模拟的方法分析了在不同断面尺寸及不同巷道轴线与最大水平主应力方向夹角的围岩应力及变形特征。研究表明:巷道断面尺寸及巷道轴线与最大水平主应力之间的夹角对巷道围岩的应力及变形特征有很大影响。其中跨高比的减小对巷道帮部的影响很大,使得应力集中程度及范围明显增大,应重点防护。巷道轴线与最大水平主应力之间的夹角增大会造成水平主应力在巷道两侧分布不对称,巷道顶底板的应力集中程度有所增大,且巷道变形明显。

In order to study the surrounding rock stress,plastic zone and deformation characteristics under the influence of the size and layout of roadway,theoretical analysis and numerical simulation are adopted to analyze the impact of different section sizes and angles between tunnel axis and the maximum horizontal principal stress direction on stress and deformation characteristics of surrounding rock.The results show that the roadway section size and the angle between the tunnel axis and the maximum horizontal principal stress have a great effect on stress and deformation characteristics of surrounding rock. The decrease of span- depth ratio has more influence on the sides of roadway,and makes the stress concentration degree and range increase,which should be concerned mainly; the increase of angle between tunnel axis and the maximum horizontal principal stress can cause horizontal principal stress asymmetry on both sides,and increase the stress concentration degree in roof- floor,which makes the roadway deformation become obvious.