敞开式TBM大坡度掘进施工特征研究

Research on Construction Characteristics of Open TBM with Large Slope

鉴于矿井采用斜井开拓方式,TBM开挖过程难免遇到地层应力随掘进轴线而变化的工况。为探究敞开式TBM斜井掘进期施工特征,本文以实际工程为背景,针对现场监测条件不足等难题,并考虑各施工部件材料几何特性及掘进步序,建立三维数值模型对施工动态进行全面把握。数值模拟结果表明:TBM在大坡度掘进施工时难免对周围岩层造成影响,围岩位移场及应力场分析为超前施工与加固提供了技术支持;喷射混凝土其内力处于允许范围,通过分析锚杆、锚索应力特征可推断出超前加固的重要性;规范施工是保证大坡度TBM快速掘进的基本前提。

In view of the mine adopts inclined shaft development mode,the stress will inevitably vary with the axis of the tunnel during the TBM excavating.In order to explore the open TBM construction characteristics of inclined shaft tunneling period,based on the actual project as the background,and aiming at the difficulties such as insufficient field monitoring conditions,a three-dimensional numerical model is established to fully grasp the dynamic construction.The model established in this paper takes into account the material geometry characteristics and excavation progress of each construction component.The simulation results show that TBM will inevitably affect the surrounding rock strata during the construction of large slope engineering.The displacement and stress fields of surrounding rock provide technical support for advanced construction and reinforcement.The internal force of shotcrete is within the allowable range,and the importance of this process can be deduced from the analysis of the stress characteristics of anchor bolt and anchor cable.Standard construction is the basic premise to ensure the rapid construction of TBM with large slope.