Damaged plasticity modelling of concrete in finite element analysis of reinforced concrete slabs

Abstract

Two interior slab-column connections, previously tested, are analysed using 3D nonlinear finite element methods. These slabs were tested under vertical monotonically increasing imposed displacement through the column till failure. One slab specimen was without shear reinforcement that failed in punching shear, while the other slab had punching shear reinforcement and failed in flexure. Both specimens are analysed using the concrete damaged plasticity model offered in ABAQUS. Concrete damaged plasticity model is employed with the fictitious crack model based on the fracture energy; where different failure mechanisms are predicted for tension and compression. Damage can be introduced in the model and it is defined separate in compression and tension. The model can be also equipped with viscoplastic regularization that provides additional ductility in the structure and helps to overcome convergence problems that have been created by cracking and strain localization that relies on the smeared crack approach. Parametric investigation based on the material and plasticity parameters is performed for the specimen without shear reinforcement. All numerical results are compared to the test results in terms of loaddeflection responses and crack patterns. Finite element analysis results are in good agreement with the experimental results and can give an insight into the failure mechanisms and crack developments of each slab. The predictive capability of the calibrated models confirms their ability for parametric studies examining the punching shear behaviour of reinforced concrete slabs with and without shear reinforcement.