With advancement of science and technology and continuous innovation of construction techniques, construction of tunnel projects under complicated geological conditions becomes possible, and more and more highway or railway tunnels cross through coal seams. Since high-gas pressure may exist in coal seams, tunnel construction may induce gas disasters, which seriously threaten the safety of tunnel construction. Dependent of some railway tunnel, this paper establishes a model by means of FLAC3D software to research influences of section size on stability of high-gas tunnel wall rocks. The results of research show that the creepage rate of gases accelerates with increase of section size of tunnel excavation, the plastic zone in wall rocks ahead of tunnel face is closer to coal seams, and the risk of outburst of gases becomes higher.%随着科技的进步和施工技术的不断革新,在复杂地质条件下建设隧道工程便成为可能,且公路隧道或铁路隧道穿过煤层的情况也越来越多. 由于煤层中可能存在高瓦斯压力,故隧道施工可能诱发瓦斯灾害,其严重威胁隧道施工安全. 以某铁路隧道为依托,利用FLAC3D软件建立模型,研究断面尺寸对高瓦斯隧道围岩稳定性的影响.研究结果表明:随着隧道开挖断面尺寸的增加,瓦斯气体的渗流速度越大,掌子面前方围岩中塑性区就越接近煤层,发生瓦斯突出的风险也就越高.
展开▼
