地质构造是影响岩爆的一个重要因素,本文以大瑞铁路高黎贡山深埋隧道为例,在野外地质调查、实测地应力分析、室内岩石力学测试分析的基础上,采用ANSYS软件模拟了在现今构造地应力场中,在褶皱和走滑断层等不同构造部位的岩体中进行隧道开挖所引起的应力重分布特征,对在复杂地质构造地区挤压和剪切构造环境下深埋隧道的岩爆特征进行了深入分析和研究,并就可能发生岩爆的部位和岩爆强度进行了预测.研究表明,岩爆发生强度与隧道所在地质构造体中的不同部位具有较大关系:当隧道位于背斜轴部和褶皱翼部且隧道轴线与褶皱轴线相平行时发生岩爆的可能性最大,而当隧道轴线与褶皱轴线相垂直时发生岩爆的可能性较小;与隧道轴线平行的走滑断层对隧道开挖后围岩应力重分布有较大影响,局部岩爆可能性较大.隧道规划建设宜选择在隧道轴线与褶皱轴线相垂直或远离断层方向等部位,有利于减弱岩爆对工程的影响.%The geologic tectonic stress field is an important factor that affects the rock bursts. Based on field geological investigation, the actual crustal stress analysis, the laboratory rock mechanics test analysis, and with the example of the deep buried Gaoligong Mt. tunnel, the paper make deeply analysis and research on the deep buried tunnel's rock burst characteristic between the extrusion and shear tectonic environment in the complex geologic tectonic stress field. Using the ANSYS software, the paper has simulated the stress reclassify characteristics at different sections of fold and strike-slip fault geology mass caused by the tunnel excavation, under the current crustal stress field, and made possibly prediction on the rock burst spot and the rock burst intensity. The research indicated that the rock burst has some intensity with the position between the tunnel and the geologic structure body, when the tunnel axis and the axial line of the fold are parallel, and tunnel located at anticlinal shaft and fold limb department, the rock burst possibility is to be the biggest; but when the tunnel axis and the axial line of the fold are vertical, the rock burst possibility is to be low; the strike-slip fault have great affects to the stress redistribution after tunnel excavation, and the partial rock burst possibility is big. The tunnel plan and construction may select the position that the tunnel axis is vertical to the fold axis or the position that far away from the strike-slip, and it is advantageous to weakening influence of the rock burst.
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