Anti-collapse mechanism for vault in tunnel

The utility model belongs to the technical field of tunnel construction, and particularly relates to an anti-collapse mechanism for an arch crown in a tunnel, which comprises a first arched beam and a second arched beam, a first sliding chute is arranged on the surface of one side of the first arched beam, and a second sliding chute is arranged on the surface of one side of the second arched beam. Arc-shaped supporting plates are slidably connected to the inner walls of the first sliding grooves and the inner walls of the second sliding grooves. According to the anti-collapse mechanism for the vault in the tunnel, the moving mechanism is arranged, according to the collapse position condition of the top of the tunnel, rotation of an output shaft of a servo motor drives a bevel gear to rotate, rotation of the bevel gear drives a transmission shaft to rotate through meshing with another bevel gear, and rotation of the transmission shaft drives a driving gear to rotate; and rotation of the driving gear drives the