斜井圆巷围岩开挖面空间效应分析

Analysis of the excavation face effect of surrounding rocks in inclined shaft

在斜井圆巷工程的力学模型中,斜井倾角的存在对开挖卸荷过程中围岩的受扰动情况有一定的影响.基于工程现场勘探资料,采用FLAC 3D有限差分法进行数值模拟,考虑不同的岩性条件,分析静水压力下斜井开挖过程中围岩的力学效应,获取开挖过程中围岩径向位移沿井轴方向的变化规律.结果表明,斜井开挖面空间效应范围与围岩的位置有关,围岩顶板受开挖面影响最大,监测断面距开挖面6倍巷道半径的距离时围岩顶板已经开始受到扰动,开挖面远离监测断面8倍巷道半径的距离时开挖面空间效应的影响方可忽略,对围岩底板的影响最小.对斜井围岩开挖卸荷过程中围岩受扰动的特征及其理论的研究,具有重要的理论意义和工程实践价值.

In the mechanical model of inclined shaft, the inclined angle has an impact on perturbation of surrounding rocks during excavation. FLAC 3D finite difference method is used for numerical simulation based on field exploration data. By Considering different lithological conditions,the mechanical effect of surrounding rock of inclined shaft during excavation under static water pressure is analyzed,and the variation of radial displacement of surrounding rock along well axis direction during excavation is obtained. Results from numerical simulation indicates that the spatial effect range of inclined shaft excavation face is related to the position of surrounding rock： the surrounding rock roof is affected mostly by the excavation face,when the monitoring section is 6 times of the roadway radius from the excavation face, the surrounding rock roof begins to be disturbed, when the excavation face is far away from the monitoring section 8 times the radius of the roadway, the influence of the spatial effect of the excavation face can be ignored.The influence on surrounding rock floor is the least. It is of great theoretical significance and practical value to study the perturbation of surrounding rocks during excavation in inclined shafts,which has important theoretical significance and practical engineering value.