3D finite element model for hybrid FRP-confined concrete in compression using modified CDPM

Abstract

The main goal of the work herein presented is to propose an accurate three-dimensional finite element model to predict the compressive behaviour of hybrid FRP-confined concrete. This was achieved through the modification of the concrete damaged plasticity model (CDPM) available in ABAQUS software, since the original CDPM has shortcomings that make it unusable to predict the compressive behaviour of confined concrete. It was demonstrated that, by turning the yield function and the flow rule dependents on the confining pressure, it is possible to use the model referred to and obtain accurate results. An analytical model was used to obtain the input parameters needed to calibrate the CDPM. A specific user subroutine was developed to modify the original CDPM. Hybrid FRP properties were calibrated as well, using an appropriate analytical model. Plasticity was assumed in the hybrid combinations for which pseudo-ductile tensile responses occurred. The performance of the proposed CDPM was validated using both experimental results and analytical predictions. It was concluded that, by using the developed 3D finite element model for hybrid FRP-confined concrete in compression, a very good agreement between experimental, analytical and numerical compressive stress-strain and lateral strain-axial strain curves is reached.

Parametric Investigation of the Effects of Localization and Slenderness on the Stress–Strain Response and Confinement Efficiency in FRP-Wrapped Concrete Cylinders

“…Finite element models have been used over the last twenty years to model the structural response of FRP-confined concrete sections of various geometries and types of reinforcement and confinement with two objectives: (i) modeling the apparent stress-strain relationship or structural response of the confined concrete columns, as well as (ii) predicting the failure load and mode of failure . The most popular FEM software package used was ABAQUS, for its choice of standard material models and the flexibility offered by its materials' subroutine [38,[42][43][44]48,[51][52][53][54][55][56][58][59][60]. Other FEM codes were also used, such as ANSYS [39,57], LS-DYNA [45], DYNA3D [37], PRECON3D [41] and MASA [46].…”

“…Other FEM codes were also used, such as ANSYS [39,57], LS-DYNA [45], DYNA3D [37], PRECON3D [41] and MASA [46]. The key, however, to modeling the complex behavior of concrete is the choice of material model, and many models have been used, with the Drucker-Prager [40,47,48,57] and Concrete Plasticity Damage models [42,51,[54][55][56][58][59][60] being the most popular; in addition, Mohr-Coulomb has been used [41], a microplane material model has been used [46] as well as an adapted CAM-CLAY model [53]. Most of the proposed models achieved acceptable to good agreement with experimental data and contributed to the understanding of the field; however, many of these models are highly elaborate or were developed for particular geometries and conditions.…”

Mesoscale Study on Dilation Behavior of Plain Concrete under Axial Compression

“…At the same time, the secant strain ratio grows slowly and approaches its critical value with the increase in axial strain. The volumetric strain is an important parameter to illustrate the failure process of concrete, and its definition is shown by Equation (19). Figure 11a depicts the stress-volumetric strain relationship of the specimens with different strengths under axial compression.…”

“…Although relevant studies have been carried out, no theoretical formula for the dilation of plain concrete has been put forward in the above literature. In FRP-confined concrete, the confinement enhances the strength and ductility of concrete [15][16][17][18][19]. The performance of the developed model depends on how well it captures the dilation tendency of concrete.…”

Sustainable FRP-Confined Symmetric Concrete Structures: An Application Experimental and Numerical Validation Process for Reference Data

“…Thus, numerical methods with strong background knowledge of FEA are more efficient and convenient tools to be used for engineering research [26]. The structural performance of FRP-confined concrete was accurately predicted by FEA models [27][28][29][30][31].…”