Verification of the reinforced concrete beam model based on the results of a full-scale experimental study

Abstract

The article presents the results of a numerical experiment consisting in a bending test of a reinforced concrete beam and comparison of the results obtained with the results of full-scale experiments. In most cases, it is not possible to adequately consider all types of nonlinearities when using simplified bar and plate elements. The problem can be solved by using more detailed computational models with solid finite elements, allowing to consider directly the joint behavior of reinforcing bars and concrete. The studies were carried out in the LS-DYNA software package, which implemented the nonlinear concrete model – Continuous Surface Cap Model (CSCM). This model allows to consider the joint behavior of reinforcing bars and concrete, using bar (for reinforcing bars) and solid (for concrete) finite elements, thereby helping to overcome existing shortcomings in the diagrams of concrete behavior. As an object of modeling, a reinforced concrete statically determinable beam of rectangular section with dimensions of 1,000 х 50 х 100 (h) mm is considered. The conducted studies showed that the ultimate load on the beam based on the results of numerical modeling is quite consistent with the experimental value (8.5% discrepancy). The arrangement of cracks and the fracture pattern obtained from the modeling results in the LS-DYNA software package are in good agreement with the results of the tests. The LS-DYNA software package will allow correct solid modeling of bending reinforced concrete elements with specification of nonlinear diagrams of concrete and reinforcing bars deformation and can be used for research, calculation and design of reinforced concrete elements of buildings and structures.