Abstract
Abstract
The objective of this study is to estimate the influence of web openings in reinforced concrete deep beams by using nonlinear finite element analysis. Concrete represented by isoperimetric eight nodes, serendipity plane stress, elements. The reinforcement treated as embedded elements and considered as elastic perfectly plastic. New constitutive models to simulate concrete material suggested by means of a nonlinear regression analysis of many experimental data by using SPSS 16 – statistical program. Strain hardening approach was employed to model the compressive behavior of high strength concrete. In tension two models were used to model high strength concrete in the pre – peak and post peak states. A smeared fixed crack approach of cracked concrete in tension is assumed. Three variables included concrete strength, shear span – to – depth ratio and the width and depth of openings. The results indicated that the ultimate strength is remarkably decreased in deep beams with openings rather than deep beams. Experimental results for reinforced high strength concrete deep beam with openings compared with the finite element results and showed good agreement.
Keywords: Deep beam, Finite element, High strength concrete, Nonlinear analysis, Openings, New constitutive models.
