Dynamic behavior of a compressed reinforced concrete column with regard to the loading prehistory

Abstract

In recent years, numerous studies of the resistance of structural systems and their substructures to progressive collapse in case of failure of a load-bearing element have been conducted all over the world. Aspects of resistance to progressive collapse of reinforced concrete frames that have not been investigated to date include the consideration of changes in the mechanical and deformational characteristics of the material over time. Therefore, in this study, the analytical solution of the problem of longitudinal bending of a compressed reinforced concrete element under dynamic loading taking into account the initial stress-strain state from the preceding long-term loading based on the viscoelastic model is constructed. Numerical solution of the problem by the Runge-Kutta method is considered. It was found that the calculation results for different integration steps turned out to be similar. However, the calculation results for the integration step of 0.005 s differed by 22.3% from the calculation results for the step of 0.001 s. The difference in the calculation results for integration steps of 0.001 and 0.002 s did not exceed 1.3%.