正帮矿胶带大巷机头硐室扩刷变形分析及控制

Deformation analysis and control of machine head chamber expanding of belt main roadway in Zhengbang Mine

为解决由巷道扩刷而引起的大断面围岩控制难题,以正帮矿胶带大巷机头硐室扩刷施工为背景,结合理论分析、工程类比及数值模拟等方法,对扩刷巷道进行变形分析并研究其围岩控制技术。结果表明当喷层厚度达到150 mm时,围岩应力松弛区较小且塑性区深度普遍小于2.2 m。锚杆间距较大时(0.8~1.2 m),承压拱保持较低应力值;随着锚杆间距逐渐减小(0.8~0.4 m),承压拱承载能力呈幂函数形式快速增长。基于上述研究,并结合现场生产地质条件提出了锚网喷联合支护技术方案,并进行现场工程应用,实现了对扩刷巷道的稳定性控制。

In order to solve the control problem of large section surrounding rock caused by roadway expansion,the expansion construction of head chamber of belt main roadway in Zhengbang Mine was taken as the engineering background,combined with the methods of theoretical analysis,engineering analogy and numerical simulation,the deformation of the expansion roadway was analyzed and its surrounding rock control technology was studied.The results showed that when the thickness of shotcrete layer reached 150 mm,the stress relaxation area of surrounding rock was smaller and the depth of plastic area was generally less than 2.2 m.When the anchor spacing was large(0.8~1.2 m),the bearing capacity of the pressure arch kept low stress value;with the anchor spacing decreasing(0.8~0.4 m),the bearing capacity of the pressure arch increased rapidly in the form of power function.Based on the above research,combined with the geological conditions of production,the technical scheme of bolt net spray combined support was given,and the field engineering application was used to realize the stability control of the extended roadway.