Experimental and numerical study on seismic behavior of prestressed concrete composite shear wall

In this study, a novel type of prestressed concrete composite shear wall is proposed. The proposed shear wall consists of two precast prestressed concrete slabs with steel trusses and in-filled concrete. The thickness of this precast slab was reduced to 35 mm, and the weight was correspondingly reduced. The prestressed steel in the precast slab acted as horizontal steel in the composite shear wall, thereby improving the shear resistance of the composite shear wall. Four prestressed concrete composite shear walls and one cast-in-situ shear wall were tested under cyclic loading to study the seismic behavior. The seismic behaviors, including failure modes, hysteretic curves, stiffness degradation, and energy dissipation, are analyzed and compared. The effect of the type of boundary element on the composite shear wall was also examined. The test results revealed that the composite shear walls had almost the same seismic performance as the cast-in-situ shear wall. Compared with the cast-in situ shear wall, the energy dissipation capacity of the composite shear wall was enhanced. The horizontal prestressed steel in the composite shear wall reduced diagonal crack propagation. Among the prestressed concrete composite shear walls, specimen PW1, whose boundary elements were completely cast-in-situ, exhibited better seismic performance. To investigate the effects of the axial compression ratio and initial prestress level on the seismic performance of the composite shear wall, a finite element model was established for the cast-in-situ shear wall and prestressed concrete composite shear wall. The analysis results indicated that under a high axial compression ratio, the bearing capacity and ductility of the composite shear wall were higher than those of the cast-in-situ shear wall. Under a higher axial compression ratio, the ductility of the composite shear wall improved as the initial prestress increased. Above all, the proposed prestressed concrete composite shear wall is suitable for practical projects.