Numerical simulation of typical earthquake surface rupture in Wenchuan earthquake-with main street of Xiaoyudong town as an example

According to the investigation of typical earthquake surface rupture in main street of Xiaoyudong town, this paper studies the stress distribution state near the surface rupture of earthquake in main street of Xiaoyudong town using two-dimensional finite element numerical simulation software of MIDAS/GTS, thereby fits the actual impact range of seismic deformation zone to buildings damage. The results show that the site is overall upward under earthquake, both displacement and stress are greater in hanging wall of fault than in fault footwall and top-down change law of displacement is reverse with stress change. After earthquake, hanging wall of fault deflects to footwall fault, the deflection results in strong tensile stress in hanging wall of fault, thereby easily generates tension crack in houses and ground. The maximum principal stress vector direction is some oblique or some vertical. On the ground, the maximum principal stress vector is parallel to the ground and the maximum principal stress and shear stress appear the maximum value near fault.