Application of Drucker-Prager Plasticity Model for Stress-Strain Modeling of FRP Confined Concrete Columns

Department of Building and Construction, City University of Hong Kong, China
Procedia Engineering 12/2011; 14:687-694. DOI: 10.1016/j.proeng.2011.07.088


Existing research works have identified that Drucker-Prager (DP) plasticity model is capable of modeling the stressstrain behavior of confined concrete. However, the accuracy of the model largely depends on the adequate evaluation of its parameters that determine the yield criterion, hardening/softening rule and flow rule. Up to date, most research works mainly focus on the first two criteria. The plastic dilation angle is the major parameter that governs the DP flow rule. This paper addresses the plastic dilation properties of concrete for FRP confined circular concrete columns under the theoretical framework of DP model in the commercial software ABAQUS. Through careful analyses of test results for FRP confined concrete columns, it is found that the plastic dilation angle is a function of axial plastic strain and the lateral stiffness ratio. A simple model for the plastic dilation angle is subsequently developed. With the implementation of this model, the finite element analysis results fit well with the experimental stress-strain curves for columns with both low and high confinement.

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Available from: Jiafei Jiang, Apr 11, 2014
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    • "While the dilation parameter is important in determining the axial capacity and volumetric response of FRP-confined concrete, only a few studies have attempted to quantify appropriate values for the dilation parameter. Yu et al. [5], Jiang et al. [8], and Jiang and Wu [6] demonstrated that the concrete axial plastic strain during the loading and the rate of confinement increment affect the shear dilation of concrete. They provided analytical models that presented the variation of the concrete dilation parameter as a function of the plastic strain and the confinement lateral stiffness ratio. "
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