| Bolt has been in wide use as a kind of support in tunneling, especially fully grouted bolt. But the design method for fully grouted bolt is limited due to the shortage of it's support effect mechanism at present. So in this thesis an in-depth exploration of the finite element simulation of fully grouted bolt will be done starting from the study of mechanics mechanism of fully grouted bolt, the result will provide reference for the design of fully grouted bolt and this have value of theory and engineering.Firstly, an in-depth exploration of the mechanics mechanism of fully grouted bolt will be done based on the comprehensive analysis of the factors to affect the stability and the failure modes of tunnel, this will lay the foundation for the following study of the finite element simulation of fully grouted bolt. Secondly, in view of the limitation and shortage of traditional simulation of finite element approaches for bolt, a new composite grouted bolt element including nonlinear contacting relation will be built based on the above study of the mechanics mechanism of fully grouted bolt. Then, an elastic-plastic finite element program will be developed for the analyses of tunnel stability, in which the composite grouted bolt element and nonlinear finite element analysis method will be used; The patterns and the affect of main design parameters on the support effect of bolt will be analysed using the program, and conclusions of guidance importance for tunnel support design will be drawn. Finally, simulation compution for the excavation and support of a highway tunnel will be made out using the above production, and the method of application of the program will be discussed; Analysis of the deformation, stress and distribution of plastic range will be done, and rational support plan will be worked out, which is of guidance importance for tunnel support design and the thery and technique of fully grouted bolt used in tunneling will be perfected further.
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