Abstract
The great earthquake in 1978 caused severe damages to buildings and infrastructures in Japan. On a basis of the lesson learned from the damages, the Japanese Building Standard Act was revised in 1981. Being insufficient seismic capacities of those buildings built before 1981, it is politically encouraged to improve structural properties which are specified stiffness, strength and ductility. We performed the lateral loads test of a frame specimen retrofitted by steel brace without anchors to confirm the effect of the seismic retrofit. And the frame specimens were modeled, the finite element analyses were performed and grasped the relationship between story shear force and story displacement, the failure behavior and stress distribution of the model in detail. The results of analyses were suited the tests approximately, we proposed the resistant mechanism to shear force transfer of seismic strengthened RC frames with steel brace considered the grout stress.
