Experimental study on seismic behavior of double-skin composite wall with L-shaped connectors

Abstract

In this paper, the authors' research group propose a novel double-skin composite wall (DSCW), which is composed of boundary columns, steel faceplates, L-shaped connectors and infill concrete. To further study the seismic performance of DSCW specimens, six high shear-span ratio DSCWs were designed and manufactured for a quasi-static test. In the experiment, the welding spacing, welding forms, and the thickness of the steel faceplate are used to set forth parameters; moreover, the failure mode, deformation performance and energy dissipation capacity of the DSCWs are analyzed. Test results show that the failure mode of each specimen was flexural failure, as shown by the fractured steel plate at the bottom of the boundary columns, the crushed infill concrete at the tear, and the specimens' buckled steel faceplates in different degrees. The average value of the yield drift ratio was 1/177; the average value of ultimate drift ratio was 1/39, and the average value of displacement ductility coefficient was 4.46. A good energy dissipation capacity was shown by the specimens as it increased gradually during the testing process. The results show that the local buckling of the steel faceplate can be delayed by reducing the welding spacing and adopting the blossom-form or dense bottom welding arrangement; thus, improve the ductility and energy dissipation capacity of the specimens. When the thickness of the steel faceplate is increased, the local buckling of the steel faceplate is less likely to occur, and the bearing capacity is improved. Based on the theoretical analysis, a buckling stress calculation model is proposed to calculate the buckling stress of the steel faceplate at the bottom of the specimen.