predicting the compressive stress–strain curve of frp-confined concrete column considering the variation of poisson’s ratio

As it is well known, poisson’s ratio of concrete is not constant during a loading process, but increases with increasing compressive loading. in this study, the effect of poisson’s ratio and its variation on the compressive behavior of frp-confined concrete is investigated using finite element (fe) analysis. the concrete triaxial behavior was modeled using plasticity theory and damage mechanics. buckling of longitudinal rebars and bending of transverse rebars were included in the model. because of the software limitations for applying the variation of poisson’s ratio during the loading process, a stepwise procedure is proposed. for the sake of verification and corroboration of the results, for column samples under different confining and reinforcing conditions, the available test data in literature were examined. the data set contains 25 frp-confined normal strength concrete columns with different number of frp layers with or without steel reinforcement. the results of this study demonstrate the importance of considering the variation of poisson’s ratio in 3d finite element analysis of confined concrete. comparing the results obtained from the proposed model with the available test results in the literature shows that the average absolute error (aae) of the proposed model is less than 14% with standard deviation (sd) of 6.16%. therefore, the capability of this model in estimation of the entire compressive stress–strain curve of concrete columns over a wide range of confining conditions is acceptable.