Experimental Investigation on Cyclic Behavior of Butterfly-shaped Links Steel Plate Shear Walls

An innovative type called "butterfly-shaped links steel plate shear wall (BLSPSW)" was proposed as a lateral load resisting system. In this novel system, by creating butterfly-shaped links in the four sides of the web plate, the lateral load resisting mechanism is not the development of a diagonal tension field on the web plate (similar to Conventional SPSWs), but the capacity of the system is determined by the shear strength of the links. Therefore, the geometric parameters of the link as initial design inputs affect predicting and controlling the stiffness and strength of the BLSPSW. Three experimental specimens were loaded to examine the behavior of the proposed system. The first one was the conventional steel plate shear wall (called SPSW-1), and two others prepared of the butterfly-shaped link steel plate shear wall (BLSPSW) with links that have been controlled by shear yield (SPSW-BL 80) and flexural yield (SPSW-BL 130). The experimental results showed that the stiffness and strength of the BLSPSW specimens can be controlled by the link geometry. Also, the BLSPSWs indicated desirable ductility up to 10 percent and high energy dissipation, even in small drifts compared to the SPSW-1. At last, the shear strength formulation of the butterfly fuses was used to determine the shear capacity of the BLSPSWs and compared with the experimental results.