公路隧道穿越采空区群稳定性分析及加固措施研究

Stability Analysis and Reinforcement Measures of Highway Tunnel Crossing Goaf Group

煤层采空区群受地层岩性、开采工艺和时间效应等影响,具有隐蔽性强、规律性差、岩体软弱和空间变异性等特点,若处置不当,将对隧道施工安全产生严重威胁。采用现场调查、物探和钻探法综合确定采空区群的空间形态。采用MIDAS/GTS NX有限元软件建立隧道穿越煤层采空区群三维实体模型,针对采空区群的特点、采空区类型及加固措施的可行性,研究隧道穿越采空区群未加固和加固后的围岩位移、塑性区变化规律及稳定状态,分析不同类型采空区加固措施对隧道稳定性的改善效果,提出采空区围岩的加固方法,并对其进行现场验证。

Due to the influence of stratum lithology,mining technology,and time effect,the coal seam goaf group has the characteristics of strong concealment,poor regularity,weak rock mass,and spatial variability.If it is not handled properly,it will pose a serious threat to the safety of tunnel construction.The spatial form of the goaf group is determined by field investigation,geophysical prospecting,and drilling methods.The MIDAS/GTS NX finite element software was used to establish a three-dimensional solid model of the tunnel crossing the coal seam goaf group.According to the characteristics of the goaf group,the type of the goaf and the feasibility of the reinforcement measures,the displacement of the surrounding rock,the change law of the plastic zone,and the stable state after the tunnel crossing the goaf group with and without reinforcement are studied.The effect of different types of goaf reinforcement measures on the stability of the tunnel is analyzed,and the reinforcement method of the surrounding rock in the goaf is proposed and verified on site.