Seismic performance of a novel partly precast RC shear wall with double precast edge members and a central T-shape CIP member

A novel partly precast shear wall was proposed in this study to accelerate construction and further reduce the weight of precast components for high-rise building structures. The proposed wall consisted of double precast edge members and a central cast-in-place (CIP) member. The rebar splice was achieved by the grout-filled sleeve connection for the precast members and lap splice connection for the CIP member. The seismic performance of the proposed wall was investigated through a full-scale experimental program, in which three specimens were designed and tested under the combination of a constant axial load and cyclic loads, including two identical proposed walls and a CIP wall as a reference. The axial load was applied to achieve a high axial load ratio of 0.5. Based on the test results, it was found that the proposed walls were subjected to similar damage progression and failure mode with the CIP wall. All failed due to concrete crushing, shear cracking and rebar buckling at the base corners of walls. The only difference was that the proposed walls would experience additional vertical cracks along the interface between the precast and CIP zones due to insufficient bond strength between at the interface. It was also found that under the high axial ratio of 0.5, the proposed walls would have comparable seismic performance with the CIP wall in terms of deformability, ductility and lateral load capacity. In addition, the two identical proposed wall had similar seismic performance indicating the good repeatability of test data and stable performance of the walls. Therefore, the proposed walls can have satisfactory seismic performance during a seismic event and could be an effective alternative method for the CIP walls if designed appropriately.