A Two-Stage Seismic Resisting System Consists of Knee elements and Vertical Link Beam

This paper presents a new dual seismic-resisting system, consists of a Vertical Link Beam (VLB), and a couple of knee elements which are connected in series using chevron bracing called Chevron Knee-Vertical Link Beam (CK-VLB)Subjected to moderate earthquakes, vertical link beam exclusively dissipates the earthquake energy through plastic shear distortion, while the other structural elements remain in elastic range. Under strong earthquakes, plastic deformation of VLB will be halted by thestopper and subsequently cause yielding of the knees. To investigate the seismic behavior of the system, finite elements models are developed using ABAQUS structural analysis software Considering the knee yielding mode, suitable shape and angles for diagonal knee bracing is proposed. Monotonic and . cyclic analyses have been conducted to compare dissipation capacities on three individual models of passive systems. A bilinear kinematic hardening model is incorporated to trace the material nonlinearity