| The seismic behavior of Reinforced Concrete (RC) frames can be improved byretrofitting with energy-dissipation braces. Concrete beams often act as energy-dissipationbeams in traditional eccentrically braced structures, which easily leads to concrete beams’brittle failure and difficult repairing in earthquake. In Y shape eccentrically braced framestructures, the beams and floors linked with energy-dissipation beams are apt to destroy,though its energy-dissipation beams are transferred to internal. Adding energy-dissipationdevices to RC frames can effectively absorb and consume the earthquake energy, delayeven avoid main structures’ damage, but expensive.A new cross shape energy-dissipation braced Reinforced Concrete (RC) frames wasproposed after combining advantages of Y shape eccentrically braces andenergy-dissipation braces to retrofit RC frames. A test model of one-story and one-bay RCframe retrofitted with above cross brace is designed and conducted low-cyclic reversedload tests, its mechanical behavior of energy-dissipation beam and seismic behavior suchas capacity, ductility, stiffness and energy-dissipation capability are studied. The resultsshow that the steel bracing-retrofitting method can improve the energy-dissipating capacityand lateral stiffness of RC frame effectively. Moreover, the adopted connectionconfiguration can transfer the force of steel braces to existing frame effectively and easy toconstruct.In the paper, after verifying the validity of finite element model built in ABAQUS.The mechanical behavior, lateral strength, stiffness degradation and energy-dissipationcapacity of this cross shape braced RC frames were discussed in detail after comparisonwith the Y shape eccentrically braced RC frames and pure RC frames. The results showthat the cross shape energy-dissipation braced RC frames perform better in lateral strength,stiffness degradation and energy-dissipation capacity.This paper also gives contrastive analysis of some parameters that may affect strength,stiffness, ductility and energy-dissipating capacity of the structure. These parametersinclude energy-dissipation length, height-to-thickness on web, width-to-thickness on flangeand Stiffener’s Space. |
