International Concrete Abstracts Portal

Title: Shear Behavior of Reinforced Concrete Deep Beams

Author(s): Kamaran S. Ismail, Maurizio Guadagnini, and Kypros Pilakoutas

Publication: Structural Journal

Volume: 114

Issue: 1

Appears on pages(s): 87-99

Keywords: compressive strength; deep beams; shear reinforcement; shear span-depth ratio; size effect

Date: 1/1/2017

Abstract:
This paper presents an experimental investigation into the structural behavior of 24 reinforced concrete (RC) deep beams examining parameters affecting shear capacity such as shear span-depth ratio, concrete compressive strength, web reinforcement ratio, and effective beam depth. The results reveal that concrete compressive strength and shear span-depth ratio have the most significant influence on the behavior and capacity of RC deep beams and the shear strength at failure is size-dependent. The test results are compared with code predictions and it is shown that the ACI 318-14 predictions are conservative for normal-strength concrete, but unconservative for high-strength concrete beams, while AASHTO LRFD is slightly unconservative for beams with shear span-depth ratios less than 1. The EC2 and Model Code 2010 predictions are shown to be conservative overall, but the degree of conservatism decreases with increasing concrete strength. It is concluded that for improved prediction efficiency, current strength reduction factors used in design guidelines for inclined concrete struts need to include all three main parameters: concrete strength, shear span-depth ratio, and shear reinforcement.