The effectiveness of welded inclined bars as shear reinforcement in rectangular beam

Abstract

The use of bent-up bars as shear reinforcement has received little preference from the designers due to the unavailability of space for the anchorage, and also due to the insufficient number of mid-span bars to be bent-up in the shear region near the supports. Welded independent inclined bars (WIB) are not affected by these two shortcomings. This report presents the results of laboratory test on rectangular reinforced concrete beams in which the effectiveness of WIB as shear reinforcement were studied In order to investigate the influence of the quantity, spacing and the inclined angle of the WIB on the shear capacity of the beams, five beams were tested. All the beams were identical in size and quantity of flexural reinforcement. The control beam was provided with vertical links, while the other four were provided with WIB of different amount, pitch and inclination angle to the longitudinal axis of the beams. The specimens were tested to failure and their performance was measured in terms of ultimate load, deflection and crack patterns. The results obtained show that all the beams with WIB achieve larger ultimate loads than the control beam. It also reveals that the beams with larger quantities of WIB and larger inclination angle are stronger in shear that they failed in flexural. The results suggest that the WIB can be applied as shear reinforcement in the design of rectangular reinforced concrete beams.