# Theoretical Investigation of Stresses and Displacement in RC Rectangular Slab

## Keywords:

Stress, Bending moment, Displacement, FEM.## Abstract

The aim of this paper is the static bending analysis of reinforced concrete (RC) rectangular slab using analytical methods, i.e. classical plate theories and finite element method (FEM). Three cases of rectangular slabs, in which the thickness of the plate varies, and they are simply supported. The bending stresses and deflection were determined by using different approaches of the classical theory of plates based on Love-Kirchhoff’s (L-K) hypothesis, then compared the achieved results to the numerical analysis-FEM results. For this purpose, the 3D-modelling and simulation, with the subsequent analysis of rectangular slab were done in ABAQUS computer program. Three-dimensional 8-node first order fully integration continuum elements (C3D8 - Bricks) are used to model the rectangular concrete slab. Also, three-dimensional 2-node first order truss elements (T3D2 - Truss) are used to model the steel reinforcing bars. Once deflection, bending moments and bending stresses are obtained by both methods, some approaches show close results with a significant difference. This difference in results can be explained by the fact, that FE analysis represents the exact model of rectangular plate (i.e. 3D model representation) which is consist of concrete and reinforcements 3D modeled slab with all properties for each material. All of these properties and the combination of materials cannot be done throw the classical plate theories equations. Also, classical plate theories depend on several assumptions, which has a significant effect on the results.

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## How to Cite

*American Scientific Research Journal for Engineering, Technology, and Sciences*,

*57*(1), 62–76. Retrieved from https://asrjetsjournal.org/index.php/American_Scientific_Journal/article/view/4972

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