Numerical Simulation Analysis of Buried Ground Fissures’ Propagation in Xi’an

Ground fissure disasters are main environmental geological hazards in Xi’an. Therefore, carrying out researches on causes of cracks and mechanisms of hazard-formative, as well as setting economical and effectively countermeasures are major geological disaster puzzles to be solved.According to the key issues existing in the ground fissure researches, we use numerical simulation analysis method to solve them. Numerical simulation analysis shows that, it is reasonable that we use elastic breaking theory to describe its rupture propagation process. This paper introduces smeared crack model and explains the fracture morphology and process of sample which has microcracks inside it. Results show that such sample’s tensile strength is greatly weakened and its tensile failure is brittle fracture. Differential subsidence movement on both sides of the buried ground fissure (fault) not only leads to upwards propagation of existing cracks, whose tendency are opposite to the existing ones, but also leads to the development of nearly vertical crack belt, which is located on the uplift block and develop from top to down. Because of width of buried ground fissures’ affected zone depends on many factors, there are still lots of work to be done on the division of buried ground fissure’s deformation zone.