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 internal friction 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.
关键词
深部巷道/注浆锚索/锚注体/算例分析/承载能力
Key words
deep roadway/grouting anchor cable/anchor grouting body/example analysis/bearing capacity
维普
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