Reference Type: Journal Article Record Number: 1 Author: Cheng, B., Su, R. K. L., Shi , C. and Yang, C. T. Year: 2015 Title: Laterally restrained steel plate with stiffeners for seismic retrofitting ofconcrete coupling beams Journal: Advanced Steel Construction Volume: 12 Issue: 2 Pages: 17 Start Page: 194 Short Title: Laterally restrained steel plate with stiffeners for seismic retrofitting ofconcrete coupling beams DOI: 10.18057/IJASC.2016.12.2.7 Keywords: Deep coupling beams, seismic retrofitting, laterally restrained steel plate, stiffener, bolt connection Abstract: Existing deep reinforced concrete (RC) coupling beams with low shear span ratios and conventionallyreinforced shear stirrups tend to fail in a brittle manner with limited ductility and deformability under reversed cyclicloading. Previous studies have developed a new retrofitting method with an unstiffened laterally restrained steel plate(LRSP) for existing deep RC coupling beams. By utilizing the post-buckling loading capacity of steel plate, thedeformability and energy dissipation of the retrofitted coupling beams were enhanced while maintaining flexuralstiffness during an earthquake. However, the occurrence of early plate buckling usually results in reduced strength,stiffness and energy dissipation capacity accompanied by significant pinching. In this study, half-scale deep RCcoupling beams rehabilitated by LRSP with stiffeners were tested. The results demonstrate that the type of boltconnection greatly influences the performance of retrofitted coupling beams. The additional stiffeners can preventplate buckling and ensure that the steel plate has a wider yield area and hence higher energy dissipation. Author Address: Associate Professor, Department of Civil Engineering, The University of Hong Kong, Pokfulam Road, Hong Kong, China