Influence of beam size and distribution of horizontal reinforcement on shear strength of RC deep beams

摘要

Twelve reinforced concrete deep beams of three different depths and two different percentages of horizontal shear reinforcement with two types of distribution were studied for understanding the size effect and influence of the distribution of horizontal shear reinforcement on the shear strength and the cracking behaviour. Three beam depths namely 300mm, 600mm and 1200mm provided with two different percentages of horizontal shear reinforcement of 0.2 and 0.3, which were distributed (i). uniformly throughout the depth and (ii). uniformly only over the middle third of the depth. The shear span-to-depth ratio was 0.75. The flexural tensile reinforcement was 1.5% and provided with 25mm clear cover. The test results showed that the mode of failure was significantly altered by changing the beam depth. Sufficient ductility was achieved in small size beams, whereas relatively very high brittleness was observed in large size beams.