盘区下向充填分层道稳定性数值模拟

Numerical simulation on stability of slicing drift of panel underhand cutting and filling

龙首矿采用下向水平分层六角形进路充填采矿法,分层道是关键通道,其稳定性至关重要。应用FLAC3D软件建立了分层道及六角形进路数值模型,应用强度等效原则确定了分层道底部配筋充填体的力学参数。分别研究了分层道假顶为素充填体和配筋充填体情况下的稳定性。结果表明,分层道开挖暴露的大面积矩形薄板,最大挠曲在中部位置,破坏方式从中部开始拉断破坏,应在开采过程中加强对顶板的支护及对中部位置的监测。此外,分层道假顶为素充填体时不利于矿山的安全生产,尤其在进路与分层道交叉巷道处,应加密配筋密度,防止出现冒落及掉块现象。

The underhand cutting and filling method with hexagon access was adopted in Longshou mine where the slicing drift is the critical path and its stability is very important.The numerical model of the slicing drift and hexagon access is built by the FLAC 3D software.The mechanical parameters of the reinforcement filling body at the bottom of slicing drift were settled through the application of the equivalent strength principle.With the artificial roof of the slicing drift either as ordinary filling body or as reinforcement filling body,their stabilities were respectively studied.The analytical results showed that the maximum deflection occurs in the central position of the exposed thin rectangular board when the slicing drift is excavated.And the fracture which is a tensile failure starts at the central position,so in the process of excavation the support of the roof and the monitoring of the central position should be strengthened.Besides,when the artificial roof of slicing drift is ordinary filling body,it will be harmful to the mine＇s safety production.Especially in the junction of slicing drift and access higher reinforcement density is needed,because the rock is prone to fall down.