Abstract: With the development of rock engineering, the influence of rock joint development on the project is drawing more and more attention; and network simulation of rock joints is an important means for this kind of problem. Mechanical models can be set up based on discontinuity network models; and then fine numerical simulating work can be carried out, which is an attractive direction in rock mechanics. Based on statistical theory of rock structure, this paper develops its own Visual Basic program for analyzing joint network simulation which can visually represents the mass distribution of joint within the rock, and can creates executable data documents which can be combined with discrete elements software. An example of an underground cavern is analyzed under the condition of static load and earthquake load; and the stress and displacement changes of the surrounding rock of cavern during different periods can be obtained. The studying method and results can be instructive to the research of deformation and failure mechanism of underground cavern surrounding rock and the design of earthquake resistant engineering

Key words: jointed rock, network simulation, discrete elements, underground cavern, stability analysis