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Anchoring technique has been widely used in slope engineering because of its reinforcing function to rock and soil mass. Yet the full understanding of the anchoring mechanism still lags behind the engineering practice. This paper introduces the design process and construction technology of the grouting anchor in slope reinforcement engineering. Based on bolt grouting test, it is found that the effective anchorage length of the grouting anchor depends on the size of the anchor solid and relative physical and mechanical properties of surrounding rock and soil. Research shows that the distribution of shear stress is uneven along the anchoring length. It mainly amasses within the front 1/3 part of the anchoring and increases with the development of outside load. The conclusion is helpful to describe the anchoring mechanism and instructive for engineering practice.

The ideal point method is a kind of multiple-goal decision analysis method, the basic idea is to construct the ideal and anti-ideal solution of multi attribute problem, with degree that near ideal solution and away from the anti-ideal solution as the basis to judge each evaluation object. Based on the basic principle of ideal point method, and comprehensive consideration of the actual geological conditions of Qingdao metro, we selected rock compressive strength, integrity coefficient, structure surface behavior, groundwater and softening coefficient as the evaluation factors of surrounding rock stability, and used the rough set theory to determine the index weight. At last, established the evaluate model for the surrounding rock stability of metro based on the rough set efficacy coefficient method. The research show that the stability analysis results are consistent with the actual excavation, so using rough set efficacy coefficient method to analysis surrounding rock stability of Qingdao Metro is feasible, which provides a new idea for the stability analysis of surrounding rock.

Based on the basic principle of the efficacy coefficient method, a model of rockburst intensity prediction was established. Considering the key affecting factors of rockburst, three factors were selected as evaluation indexes including the ratio of maximum tangential stress and rock uniaxial compressive strength, the ratio of compressive and tensile strength of rock and elastic energy index. Finally, the model was applied to the rockburst prediction of water diversion tunnel of Jiangbian hydropower station and the results show that the method is reliable, and it provids a new idea to predict rockburst.

The authors found a type of sidewall failure during the construction of a tunnel with high geostress. And relative strong rockburst usually occurred in the areas nearby during the excavation. This paper shows this type of failure called Crisp Fissure Failure and some characteristics of the failure. Reasons of the failure are also discussed. Further more, the authors studied the fracture distribution under this type of failure by Ground Penetrating Radar. Suggestions of support in a high risk tunnel are put forward based on the research of the Crisp Fissure Failure.