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Drilling and blasting method as a common excavation method is widely used in the underground engineering construction. However, in the complicated geological conditions, the path of blasting excavation available has limitation, and then the larger blasting vibration is produced, which influence the stability and safety of the protected structure. To effectively reduce the blasting vibration by optimizing the blasting excavation method, firstly, the site test on blasting vibration is conducted to obtain the blasting vibration data; secondly, the LS-DYNA software is applied to simulate the vibration generated by blasting in site test, based on back analysis on the blasting vibration, the mechanical parameters of the rock mass are obtained, and they are used to simulate six different types of blasting excavation method. According to the analysis on them, the reasonable blasting excavation method is proposed to reduce the blasting vibration which can satisfy the blasting safety regulation.

The premise of anti-explosion reinforcement design of underground tunnels is to find out the failure form and failure mechanism of anchorage tunnels to take targeted reinforcement measure sunder explosion load. However, the antiexplosion reinforcement effect of bolts(cables) on underground tunnels is seldom studied at present, and the failure law of tunnels is not clear, which cannot provide scientific basis for anti-explosion reinforcement design. In view of this, the model test apparatus for anti-explosion structures in geotechnical engineering and explosive load simulation test technology were firstly developed in this study, and based on Froude similarity theory, a series of anti-explosion model tests on different anchorage tunnels subjected to blast loads, including plane charge and mass charge, were carried out. The failure modes of several kinds of anchorage tunnels under explosion loads were obtained. Some conclusions were drawn from the model test results. Under the same test conditions, spalling occurs in tunnel roof in the plane charge test, while shear cracks and stagger cracks occur in tunnel spandrel in the mass charge test. The anti-explosion capacity of the tunnel reinforced by full-grouted bolts is better than that by part-grouted bolts. The augmentation of bolt length has no control effect on preventing crack extension in surrounding rock, when bolt spacing decreases to a certain density, it just prevents cracks from extending into the reinforced region. The local and dense lengthening bolts in tunnel spandrel can prevent or interdict cracks from extending in surrounding rock, or compel cracks to detour the reinforced region; consequently, it can enhance anti-explosion capacity of the tunnel. This study provides a significant reference for improving reinforcement measures of the underground anti-explosion structures and its anti-explosion capacity.

To research the reinforcement effect of a rock slope with group anchorage cables and the stress characteristics of pre-stressed anchorage cables in the fractured surface, the rock slope calculated model of a wedge block within the double-slide face was established by using the finite difference software according to the actual slope project combined with indoor model test. The pre-stress loss rule of the anchorage cable and the distribution of axial force and the force-transferring mechanism of the anchorage cable were analyzed during simulation. Also, based on the displacement contour and the safety factor of the calculated results, the quantitative analysis for the reinforcement effect of the rock slope with group pre-stressed anchorage cable was discovered. The results computed by the software conform with the data in the experiment, which can prove the effectiveness and correctness of parameter selection and model building.