The Key-group Systematic Anchorage Design Method For Jointed Rock Slopes

At present, the phenomenon of anchoring theoretical research and practicalengineering application of rock slope exists a serious discrepancy, theoreticalresearch has focused on the impact of the rock mass initial damage and micro-crackson the rock anchoring mechanism and anchoring effect, however, actual control ofslope stability and anchoring engineering is the macroscopic fracture and joints. Inorder to theoretical research of anchor to better guide and service in the actualengineering, we are starting from "the rock mass structure control theory", studyingthe effective of rock mass structure on jointed rock slope stability, deformation andfailure mode, anchoring mechanism and the anchoring effect. And presenting a newrock mass reinforcement method with anchoring, called the "key-group systematicanchorage design method" that be used to reinforce and retain unstable rock masseson heavily jointed rock slopes by combining anchorage and other preventions. Thekey-group systematic anchorage design method is based on the key block theory andthe limit equilibrium method, established a safer, more feasible in technically andmore economical anchorage design for reinforcing jointed rock slopes. In study, thefollowing conclusions:1. Basing on the structural classification of rock mass, a emergency anchoragemethod was established, joint spacing as a criterion, and a simple anchorage methodwas established, the quality of slope rock mass as a criterion.2. Analyzed the limitations of the key block theory in jointed rock slopestability evaluation, to solve the problem, the key block system was proposed, andcompared the differences in the key block and the key block system. Also, the vectoranalysis and geometric analysis of the key block system were introduced.3. Based on the key block theory and limit equilibrium theory,a new anchordesign theory and design method were proposed, called the "key-group systematicanchorage design method"that the key block system as the anchoring object,combined anchorage as the means, the project investment as the objective function to optimize the program of dynamic design. Described the contents of the key-groupsystematic anchorage design method, and given the design process of thereinforcement of jointed rock slope.4. Compared the key-group systematic anchorage design method with the keyblock anchoring method and tradition anchorage, described in detail superiority andsuitability of key-group systematic anchorage design method on anchorage jointedrock slope.5. A geological model and mechanical model were established based on therock mass structure and failure mode of the key block system. And an anchoragedesign method and calculation method were given of the geo-mechanical model ofthe key block system.6. Using the combined method of empirical method and inversion method ortest and inversion method, according to the key block system failure mode, todetermine the shear strength parameters of the control structure, respectively, smooth,rough and intermittent type joints.7. Taking the steep rock slope for example in Feng-Xi high speed wayRK39+800～RK40+052, Described the design ideas, methods and steps of thekey-group systematic anchorage method in practical engineering applications,illustrated the suitability and advantages of the methods on the stability evaluationand the anchoring treatment design of the jointed rock slope.