STUDY ON BI-AXIAL EARTHQUAKE RESPONSES OF REINFORCED CONCRETE STRUCTURES WITH SLIPPING TYPE RESTORING FORCE CHARACTERISTICS

摘要

In this paper, slipping type bi-axial non-linear restoring force model proposed by authors in previous study was explained firstly. The proposed model, which a tensor was used to express slipping behaviors, was an extended model of a elastic-perfectly plastic type bi-axial model that was based on an analogy to the theory of plasticity. Then earthquake response analyses with one-mass-system were carried out. One of the features of earthquake responses of bi-axial slipping model was that two-directional shear force response was radial and tended to concentrate in orthogonal direction of yielded direction. Numerical results of two-dimensional analyses were compared with that of one-dimensional analyses of a maximum displacement response in all horizontal direction. A tendency can be seen that plastic ductility ratios of two-directional analyses were a little smaller than that of one-directional analyses, and total input energies of two-directional and one-directional analyses were hardly different.