The present study investigates the mechanical behavior of a shear-type damper using a low-yield-strength circular hollow section (LYCHSD). The hysteresis characteristics and the deformation capacity of the LYCHSD should be evaluated in order to use LYCHSD as a seismic energy absorbing device. Thus, monotonic and cyclic loading tests were conducted on LYCHSD as variable parameters. The calculation method for full plastic shear strength and initial stiffness are established. The fatigue life of LYCHSD is predicted using Manson-Coffin law. In addition, FEM analysis is conducted in order to evaluate the local strain around the welding part due to the crack.
