Size Effects on Concrete Damaged Plasticity Model

The effect of size on the performance of the Concrete Damaged Plasticity (CDP) model was investigated in this paper. One of the important concerns about each material model is the maintenance of its stability and accuracy when implemented in structures with different sizes. CDP model is a powerful material model formulated for simulating the concrete behavior in the ABAQUS software. The structural engineers would like to know are the accuracy and efficiency of this material model dependent on the size of the problem which it is used for? The objective of this research is to respond to this question. A three-point-bending concrete beam with three different sizes were modeled in this study using the CDP model of the ABAQUS software. All concrete beams have a notch located in the middle part of the lower face of the beam. A similar set of the input parameters were used to define the CDP model in the three beam models. The three-point-bending test for each model was simulated using the ABAQUS standard software and the load-displacement curves and fracture models were obtained. The load-displacement curves were compared with the corresponding experimental curves. It was observed that the numerical and experimental curves have good agreement in all the three different size beams. This observation emphasizes that the accuracy and efficiency of the CDP model is not dependent on the size of the beam specimens. In other words, the same CDP input parameters can be used for modeling a specific concrete material in different structural sizes.

Keywords: Concrete damaged plasticity model, Size effects, Three-point bending beam, Numerical modeling