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Basing on the background of tunnel disater, we build the spread of mathematic dynamic model and use the dual boot rock bolt to control the surrounding rock, the following summaries were concluded.(1)At the beginning of surrounding rock deformation, when the tensile strength is reached, the rock will produce tensile fracture, the elastic energy resilience will be released. In view of the continuation media of elastodynamics, we will regard the tensile fracture as point source and build the spread elatic energy mamathematics model in elastic rock, we use the methods of mathematical physics to solve this mathematical model and get the expression of stress and displacement.(2)On the basis theory of finite element, using the software of ANSYS/LS-DYNA, we build the geometrical model of tunnel,exerte the constraint load and the dynamic loading on it and perform explicit structural dynamics analysis for underground rock mass, the result show that the numeration is the same as analytic solutions.(3)Comparing the thread of identity intensity anchor bolt and roll silk rock anchor bolt, we conclude that the efficiency of roll silk rock anchor bolt exceed the intensity anchor bolt. We analyse levorotatory no longitudinal rib roll silk pre-stress anchor supporting system, dextral all-thread etc strong bolt and compare the anchorage force of two kind rock bolt, we get the result that the anchorage force of levorotatory threaded rod body is higher than the dextral’s. It is indicated that the dual boot let pressure pipe is good for the energy release of tunnel digging, which also is good for the absorbation of energy release of surrounding rock. We analyse the engineering use of dual boot rock bolt, the result show that supporting effect is good under the dynamic load.
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