Study On Mechanism Of Bolting And Grouting Support In Very Broken Rock Renovated Roadway

Compared with liner and metal support, anchor support had a great advantage which is that it can support the surrounding rock actively. The power that anchor can support is largely depended on the mechanical characteristic of the rock to be supported. There are some reasons which make the failure of anchor support in the extremely broken tunnel. These reasons are low supporting power or failure anchor and bad anchor characteristic. Anchor and injection is a way of using anchor arm in two aspects. Anchor arm is used in providing support power and injecting material through it. The broken rock was cemented into a whole body by injection. This process can improve structure and strong mechanical characteristic of the surrounding rock. Injection not only can increase the rock's own carrying capacity, but also can provide a reliable foundation for anchor. Injection can also exploit the anchoring ability of the anchor to the broken rock, and control the big deformation in deep soft rock surrounded tunnel efficiently.A study was done to analyze the main element which affects tunnel deformation. The thesis studied through power characteristic, deforming feature and power theory of high pressure soft broken rock. Big finite-elemental digital modeling software called ANSYS was used to model the motion deforming and pressure changing of surrounding rock in different supporting situation. These situations are high pressure extremely broken surrounding rock under its own gravity, anchor support and anchor and injection support. The modeling result shows that anchor and injection support can improve the strength and carrying ability surrounding rock greatly. The support can control the deformation of rock surrounding tunnel efficiently. A analyze was done to provide a solution for extremely broken rock tunnel supporting with anchor and injection. The deforming broken situation and broken mechanic was analyzed in -440 pumping room in Wannian mine, Fengfeng mining corporation. The plane got great success through the project and get large financial and social profit.The thesis can provide a valuable solution for tunnel, big tunnel under ground and other broken rock's support.