Implementation of CSCM concrete numerical model for domestic concrete classes

Abstract

Introduction. The current normative procedure of accounting physical nonlinearity (state diagrams) in the calculation of reinforced concrete structures is presented. The mathematical model of concrete CSCM realized in the software package (PC) LS-DYNA is considered, its features are described, its limits and ways of its application are marked. The numerical model has two ways of its implementation in the calculation model: CSCM_CONCRETE – automatic (based on minimum input parameters of concrete) and CSCM – manual (input of a significant number of input parameters of concrete). Calculation results of both realizations have been compared with the experimental data obtained for beams made according to the domestic standards. Materials and methods. The objects of the study are concrete and reinforced concrete beams. Experimental data have been taken as a criterion for estimating the reliability of the obtained numerical results. The following parameters have been analyzed in the calculation model: the breaking load, the deflection under the breaking load and the failure pattern. Numerical computations were carried out using the LS-DYNA software package that enables a nonlinear dynamic analysis of structures under different kinds of loads and stresses, and a study of beam collapse under increasing loads with time. Results. It is not recommended to use CSCM model in any of its implementations for concrete beams made of B20 class concrete. For reinforced concrete beams made of class B30 concrete, both implementations coincide with the experimental data, the difference in the results for both implementations in terms of destruction load is up to 17 %. At the same time, a more accurate implementation of the model is a manual one, for which today it is rational to calculate the properties of concrete using a separate method mentioned in the text of this paper. Conclusions. The numerical results obtained for a reinforced concrete beam made of B30 class concrete indicate the possibility of applying the CSCM model in the study of reinforced concrete structures.