Abstract:
The hysteretic model parameters of reinforced concrete circular columns are identified in this paper. The test data of 76 flexural or flexural-shear failure RC circular columns from the Structural Performance Database by the Pacific Earthquake Engineering Research Center was collected as the database. A peak-oriented type of material modelled by the modified Ibarra-Medina-Krawinkler (I-M-K) material model was used as the basic hysteretic model of RC circular columns. The OpenSEES finite element platform was adopted to simulate each of the considered test data, and the corresponding hysteretic model parameters were identified. A total of 15 design parameters of RC circular columns were considered as the basic variables. Through multiple linear regression and stepwise regression analyses, the empirical relationships were developed to predict the hysteretic model parameters, which were validated by simulating three RC circular column specimens that were not included in the test database. The results show that the presented empirical equations (or values) can reasonably predict the hysteretic model parameters. The presented empirical equations (or values) also well reflected the characteristics of the strength and stiffness degradation of RC circular columns under cyclic loadings.