基于FLAC3D结构单元的联合支护效果数值模拟研究

Numerical Simulation Study on the Effects of Joint Support in Mining Structures Using FLAC3D

为探究复杂地质条件下采场底部出矿结构的稳定性,以某高地应力、软破碎矿体开采为实例,采用理论分析和数值模型研究方法构建了典型尺寸采场的数值模型,分析回采过程中应力卸荷对底部结构的影响,以及底部支护结构在开采过程中的稳定性变化情况。研究表明:随着矿体的回采,应力重分布过程中逐渐向底部结构转移,出矿进路两侧出现最大主应力达17 MPa;联合支护方案显著改善巷道围岩应力分布,使矿房底部结构应力分布更为均匀;在矿房回采的不同步骤中,由于应力的释放导致应力分布发生变化,应加强巷道中部的应力释放的控制措施和靠近拉底巷道部分的顶板支护。研究结论可为采用类似采矿方法的矿山优化采场结构参数和支护方案设计提供参考。

To investigate the stability of the bottom mining structure under complex geological conditions,taking an example of high ground stress and soft,fractured orebody mining,theoretical analysis and numerical modeling methods were used to construct a numerical model of a typical-sized stope.The impact of stress unloading during mining on the bottom structure and the changes in stability of the bottom support structure during the mining process were analyzed.Research indicates that as mining progresses,stress redistribution gradually shifts towards the bottom structure,with maximum principal stresses reaching 17 MPa along the ore extraction drives.The combined support scheme significantly improves the stress distribution around the tunnel,making the stress distribution within the stope bottom structure more uniform.During different steps of stope mining,stress distribution changes due to stress release,and control measures for stress release in the middle of the tunnel and roof support near the bottoming entry should be strengthened.The findings can provide a reference for optimizing stope structural parameters and support scheme designs in mines using similar mining methods.