MODELLING OF MATERIAL BEHAVIOUR OF CONCRETE

Abstract

Concrete is the main constituent material in many structures. The behavior of concrete is nonlinear and complex. Increasing use of computer based methods for designing and simulation have also increased the urge for the exact solution of the problems. This leads to difficulties in simulation and modeling of concrete structures. A good approach is to use the general purpose finite element software ABAQUS. In this paper a 3D model of a concrete cube is prepared using smeared crack model and concrete damage plasticity approach. In general, transition in the mode of failure from flexure failure at the static loading to shear failure at low velocity impact in reinforced concrete (RC) beams has been reported in the literature. To quantify the above-mentioned statement, a static load is applied on the beam and a drop-weight impact test programme was carried out on RC beams. Concrete is the main constituent material in many structures. The behavior of concrete is nonlinear and complex. Increasing use of computer based methods for designing and simulation have also increased the urge for the exact solution of the problems. This leads to difficulties in simulation and modeling of concrete structures. A good approach is to use the general purpose finite element software ABAQUS. In this paper a 3D model of a concrete cube is prepared using smeared crack model and concrete damage plasticity approach. The validation of the model to the desired behavior under monotonic loading is then discussed.The test results showed that no shear failure has been occurred under impact loading in statically flexure critical beams (i.e., shear to bending resistance ration greater than one) however with increasing drop-heights more localized failure with extensive concrete crushing at the impact region was observed.Impact interface (i.e., direct impact or with some interface such as steel or plywood plate in between impactor and beam) could be one reason that the change in failure mode has not been observed in the current test program. To simulate the structural impact response in details, a three-dimensional nonlinear finite element (FE) model was also developed. Numerical results agreed well with the test results obtained from current test program and from the literature.