To investigate the evolution characteristics of inrush disasters in water-rich fractured zones under coupled effects of excavation unloading and hydraulic loads, based on the Shenbai high-speed railway Xigu tunnel project, and considering different structural forms of water-rich fractured zones and the characteristics of groundwater occurrence, the evolution process of inrush disasters in tunnel was studied. A 3DEC discrete element numerical model, based on the principle of water-rock interaction in fractured rock masses, was established to explore the mode of tunnel inrush disaster under different geological structure characteristics and analyze the spatiotemporal evolution laws of fractured rock fissure propagation and groundwater seepage. The results show as follows. By introducing the bonded block modeling and fracture flow combination model, a mechanical model of water-rock interaction in water-rich fractured zones was established to reproduce the evolution process of inrush disasters in tunnels located in water-rich fractured zones. The disparities of inrush disaster modes caused by different structural forms of water-rich fracture zones are significant and the trigger conditions and manifestations of these inrush disasters are various. Under the 45° inclination angle, fragmented rock mass slides and surges into the tunnel along the footwall. While under the 90° dip, the surrounding rock extrudes to the palm face. When the dip is-45°, the surrounding rock of the vault collapses. The severity of inrush disaster in water-rich fractured zones increases with higher hydraulic heads. Under a -45° dip, the severity of water inrush disasters is most significantly affected by the hydraulic head. When the dip is -45°, the influence of hydraulic head is relatively weak, but the severity of inrush disasters is the most severe.