Equipment and method for testing watertightness of box culvert in large size

The invention discloses a large-scale water seal testing equipment and the method. The equipment comprises the pressure-adding system, the sealing system, the water filling system, the supporting system and the measuring system. The said sealing system comprises the ring sealed slot frame forming the sealing chamber with the box joint and the sealing belt. The said sealed slot frame is fixed on the supporting system. The said sealing belt is on the end of the sealed slot frame. The said pressure-adding system and the water filling system separately connect the sealed chamber. The invention forms the independent sealed chamber at the joint of the box to implement the seal testing in single-hole clearance method, which overcomes the failures of the traditional method. The whole testing equipment is simple and fast.