Yu C.-HWang S.-JChiu I.-CChang K.-C.KUO-CHUN CHANG2021-08-052021-08-052018https://www.scopus.com/inward/record.uri?eid=2-s2.0-85085485474&partnerID=40&md5=6a9e283f92a2febbd27d387fd8ecbc4dhttps://scholars.lib.ntu.edu.tw/handle/123456789/576039In engineering practice, VE dampers are often designed to remain intact under design basis shaking. Their elastic performance has been experimentally verified in many past studies. However, their possible damage and real performance under maximum considered shaking or greater earthquakes as well as their residual performance under aftershocks was rarely concerned before. This is very important for safety and functionality concerns of the structures equipped with VE dampers. In this study, first, for characterizing the viscoelastic behavior of VE dampers, the pre-damage fraction differential model was formed based on a series of performance test results considering different frequencies, temperatures, and shear strain levels less than 300%. Then, VE dampers were tested with larger shear deformation, i.e. 480%, 600%, 720%, 840%, 960%, and 1000% in order, to realize their ultimate performance. In between each shear strain level, the performance test under 300% shear strain at an ambient temperature of 20oC is performed to further regress the post-damage fraction differential model. Test results indicate that the stiffness and damping coefficient of VE dampers decrease proportionally with varying shear strain from 600% to 840%, and can remain half of the original values at least after 840% shear strain. It is also shown that the strain hardening of VE dampers at the first cycle is significant and may cause unexpected damage to structural connection members. Last, two numerical models of classic 7-story street house and 26-story new built residential building are used to verify the efficiency of adopting VE damper for retrofit and seismic mitigation purposes respectively. The results reveal that even though VE dampers will be damaged during excitations of large earthquakes, the descent functions still benefit aseismic ability to a certain extent. ? 2018 All rights reserved.Earthquake engineering; Earthquakes; Engineering geology; Shear strain; Strain hardening; Viscoelasticity; Different frequency; Engineering practices; Residential building; Residual performance; Stiffness and damping coefficients; Structural connections; Visco-elastic behaviors; Visco-elastic dampers; Structural designconference paper2-s2.0-85085485474