The influence of web openings on the structural behavior of reinforced high-strength concrete deep beams

The objective of this study is to experimentally and analytically estimate the influence of web openings in reinforced concrete deep beams. Thirty-two reinforced high-strength concrete deep beams with or without openings were tested under two-point top loading. Test variables included concrete strength, shear span-to-depth ratio, and the width and depth of the opening. Test results indicated that the strengths at diagonal crack and at peak were closely related to the angle of the inclined plane joining the support and the corner of the web opening. Also, the influence of concrete strength on the ultimate shear strength remarkably decreased in deep beams with openings rather than solid deep beams. From comparisons of predictions and test results, the equations proposed by Kong and Sharp, and Tan, Tong and Tang would be suitable for reinforced high-strength concrete deep beams with openings and θ3≥30∘θ3≥30∘.