为了解决寨崖底煤矿大断面煤巷下山支护困难的问题,根据自然平衡拱理论建立力学模型,从理论上分析了下山围岩的受力状况,并采用数值模拟软件FLAC3D分别对3~6 m不同巷宽和巷高条件下围岩的变形破坏规律进行研究。在此基础上,确定了大断面下山煤巷的2个受拉破坏区域为关键部位,提出了大断面下山煤巷整体稳定、关键部位重点加强的稳定性控制措施。实测结果表明,采用HRB335高强度锚杆配合17.8 mm小孔径预应力锚索的稳定性控制技术,可以使下山煤巷围岩变形量控制在120 mm以内,确保下山煤巷围岩的稳定性。
In order to solve the support difficult problems of the large cross section gateway dip in Zhaiyadi Mine,based on the mechanics model established with the natural equilibrium arch theory,the paper from the theoretical point,analyzed the stressed status of the surrounding rock along the dip of the seam gateway.The numerical simulation software FLAC3D was applied to individually study the deformation failure law of the gateway surrounding rock under the 3 ~ 6 m different coal pillar width and height.Thus two tensioned failure zones in the surrounding rocks of the large cross section dip gateway were determined as the key location zone.The paper provided that for the completed stability of the large cross section dip gateway,the key location should be the stable support idea to enhance the roof control.The site measured results showed that with the stability control technology of the HRB335 high strength bolt as well as the diameter 17.8 mm and small borehole pre-stressed anchor,the deformation of the dip gateway surrounding rock would be within 120 mm and the stability of the dip gateway surrounding rock could be ensured.