Experimental and Analytical Study on Reinforced Concrete Deep Beam

ABSTRACT: Several reinforced concrete deep beams with different L/D ratios (1.5, 1.6, 1.71) were cast and tested in order to investigate the strain distribution pattern at mid-section of the beam. This paper describes analysis of deep beams subjected to two point loading with three different L/D ratios (1.5, 1.6, 1.71) using Non-linear Finite element method (ANSYS 9.0 software). In ANSYS 9.0 software, SOLID 65 and LINK 8 element represent concrete and reinforcing steel bars. Non-linear material properties were defined for both elements. Using ANSYS software Flexural Strains and deflections were determined at mid-section of the beam. The failure crack-patterns were obtained. Variations of flexural strains were plotted at mid-section of the beam. The beams were designed by I.S.456-2000 (Indian Standard Code of Practice for Plain and Reinforced Concrete). Flexural strains were measured experimentally at mid-section of the beam using Demountable mechanical strain gauge. The failure crack-patterns of the beam for different L/D ratios were also observed. The comparison between ANSYS results and experimental test results were made in terms of strength, flexural strain and deflection of concrete beams. The analytical and experimental flexural strains were compared at mid-section of the beam for different L/D ratios. It was found that the smaller the span/depth ratio, the more pronounced was the deviation of strain pattern at midsection of the beam. As the depth of the beam increases the variation in strength, flexural steel and deflection were found to be more experimentally than the non-linear finite element analysis.