Banji Coalmine, China Coal Xinji Energy Co Ltd
Anhui Provincial Key Laboratory ofBuilding Structure and Underground Engineering, Anhui Jianzhu University
School of Civil Engineering, Ludong University

针对深部巷道原支护方案难以维护巷道稳定、矿方返修方案无法有效遏制顶板破碎下沉等问题,分析注浆锚索主要参数对岩体复合力学参数的影响规律,推导注浆锚索锚注体承载能力计算公式,算例分析承载能力变化规律,在此基础上,对比分析锚注返修方案和矿方返修方案控制效果。结果表明:注浆加固对复合内摩擦角提高的贡献远大于注浆锚索间排距,内摩擦角提高值由0°增加到20°时,复合内摩擦角提高率达到98.8%;注浆加固中黏聚力提高对复合黏聚力的影响远高于内摩擦角,黏聚力提高值由0MPa增加到0.8MPa时,提高率达到131.1%;复合黏聚力对锚注体承载能力影响显著,由0.61MPa增加到1.41MPa时,承载能力提高率增加到60.2%;锚注体承载能力随注浆锚索间排距的增加而降低,间排距由0.8m增加到2m时,承载能力降低率为25.5%。锚注返修段比矿方返修段顶板位移控制率提高了27.8%,控制效果显著,可以在巷道返修特别是顶板破碎地段推广锚注返修方案。

The original support plan in a deep roadway could hardly maintain its stability, and the repair scheme provided by the coal mine failed to effectively control the collapse and subsidence of the roof. In view of this problem, the influences of the main parameters of grouting anchor cables on the composite mechanical parameters of rock mass were researched first. Subsequently, the calculation formula for the bearing capacity of anchor grouting body was derived, and example analysis was conducted to explore the variation law of bearing capacity. On this basis, the control effects of the anchor grouting repair plan and the coalmine repair plan were comparatively analyzed. The results reveal that grouting reinforcement is far more contributive to the improvement of composite internal friction angle than the spacing between grouting anchor cables. As the internal friction angle increases from 0° to 20°, the composite internalfriction angle grows by as high as 98.8% . In grouting reinforcement, cohesion is superior to the internal friction angle in enhancing composite cohesion. As the cohesion increases from 0 MPa to 0.8 MPa, the composite cohesion rises by 131.1% . The composite cohesion has a noticeable impact on the bearing ca- pacity of the anchor grouting body. As the composite cohesion increases from 0.61 MPa to 1.41 MPa, the bearing capacity surges by 60.2% . On the other hand, the bearing capacity of the anchor grouting body decreases with the increase of the spacing between grouting anchor cables. As the spacing increases from 0.8 m to 2 m, the bearing capacity drops by 25.5% . Overall, the control rate of roof displacement in the anchor grouting repair section is 27.8% higher than that in the coalmine repair section, which is in- dicative of the outstanding control effect of anchor grouting. The anchor grouting repair scheme can be promoted in roadway repair practice, especially in sections with broken roofs.

国家自然科学基金项目(52374073);安徽省重点研究与开发计划项目(202104a07020019);安徽省高校优秀人才支持计划项目(gxyq2020033);中煤新集能源股份有限公司科研项目(ZMXJ-LXKY-JS-2023-15)