IN-PLANE AND OUT-OF-PLANE MECHANICAL BEHAVIOR OF DOUBLE FACED SUPERPOSED CONCRETE SHEAR WALLS

A typical double faced superposed concrete shear wall is composed of two precast concrete panels on both sides and cast-in-place concrete layer between them. It has a wide application prospect with advantages of good integrity, template and support saving, construction efficiency and saving in cost. This paper conducts in-plane low reversed cyclic loading tests under high axial compressive ratio and out-of-plane low reversed cyclic loading tests under low axial compressive ratio on full-scale concrete shear walls to investigate seismic behavior of double-faced superposed concrete shear walls. The results reveal that all four specimens fail in bending and exhibit similar hysteresis characteristics. The superposed specimens show better energy dissipation than cast-in-place (CIP) specimens. The bearing capacity of the superposed specimen is 5% higher than that of CIP specimen under in-plane cyclic loading; while the bearing capacity of the former is 12% lower than that of the latter under out-of-plane cyclic loading. Both the two superposed specimens behave in ductile manner with ductility factors of 2.15 and 3.83, respectively, which are 25% and 20% higher than that of the corresponding CIP specimens. The flexural and shear safety factors of the superposed specimens are larger than 1.1. The ultimate shear load at horizontal connection of the superposed specimen is much less than its shear capacity. In general, double faced superposed concrete shear walls show good seismic performance and can be applied in seismic regions.