Study on the Seismic Behavior of Trash Rack Concrete Frame of RCC Gravity Dam with the Reserved Groove Construction Method

In order to accelerate construction progress, reserved groove construction method is used to construct the horizontal beams which join the trash rack piers and dam body. A decrease of connection stiffness at the junctions may be caused, and the seismic behavior of trash rack concrete frame will be affected. In accordance with a certain powerhouse dam section of RCC gravity dam, the effects of weakening of connection between piers and beams on the structural seismic behavior were studied in this paper. The structural vibration characteristics, dynamic displacements and dynamic stresses were analyzed by response spectrum method. The results showed that the weakening of connection weakened the seismic behavior of superstructure in flow direction, and the seismic behavior of substructure in flow direction and lateral direction. Owing to the big stiffness of integrity structure, the weakening of connection will not affect the structure seismic behavior obviously if the weakening degree is controlled at a relative lower level.