Seismic behavior of low shear-span ratio double-skin composite wall with L-shaped connectors

Abstract

A double-skin composite wall (DSCW) with innovative L-shaped connectors was proposed, which can be simply constructed and quickly assembled to promote the development of a prefabricated steel structure. To further examine the seismic capacity of the novel DSCW, five DSCWs were designed and fabricated, each with a low shear-span ratio. The testing parameters include the welding spacing, distance between connectors, and the width-to-thickness ratio of the wall-to-steel faceplate. The failure mode of each DSCW specimen was observed, while determining the load-carrying capacity, the hysteretic curve, the skeleton curve, and the displacement ductility coefficient. Moreover, the distribution and development of the boundary column strains, steel faceplate strains, and L-shaped connector strains were researched. The test results showed that the DSCWs with a low shear-span ratio had excellent load-carrying capacity and ductility, and all specimens experienced flexural-shear failure. Decreasing the welding spacing of L-shaped connectors or reducing the distance between L-shaped connectors can enhance the capacity of energy dissipation and ductility, but such a distance reduction has a slight effect on the shear strength. When the thickness of the steel faceplate on different specimens is the same, the load-carrying capacity of the DSCW specimen obviously improves as the width-to-thickness ratio of the wall-to-steel faceplate increases. Finally, shear strength calculation formulas of the novel DSCW under the low shear-span ratio were established.