Dual moment resisting-shear link frames: experimental and numerical investigation

Abstract

Moment resisting frames (MRFs) are one of the most favorable systems, thanks to their appropriate performance and sufficient geometric flexibility. Despite these advantages, MRFs have limitations such as low stiffness and certain code limitations. This paper provides the experimental and numerical results of a novel dual lateral load resisting system. This dual system is proposed to combine the flexural and shear nonlinear behavior of MRFs with different lengths. In the proposed dual system, MRFs are combined with frames that have a shear link with a smaller cross-section at the mid-span. This combination transfers the first plastic hinges location from the beam ends of the MRFs to the mid-span of the shear link frames. Two 1/3-scale tests are performed in the strong floor lab, and the frames are tested under quasi-static cyclic loading. In addition to increasing the stiffness of the system, the novel dual system waives the code requirement to satisfy the constraint on the beam span-to-depth (span/depth) ratio. Furthermore, the new dual system improves the resilience of the system due to the substitutability of the shear link after an earthquake. Moreover, verified 3D finite element models of the moment resisting-shear link frames dual system are also used to demonstrate the performance of the new dual system.