Effect of Aggregate Type on the Shear Behavior of Reinforced Lightweight Concrete Beams

Abstract

Despite extensive research on lightweight aggregate concrete (LWAC), the precise effects of different coarse aggregate types and their physical properties on the shear capacity of reinforced all lightweight aggregate concrete (ALWAC) beams remain unclear. A comprehensive understanding of how aggregates influence the shear behavior of reinforced concrete (RC) beams is essential for accurately predicting shear strength and effectively designing ALWAC structures. To advance this understanding, experiments were conducted on twelve RC beams: four made of normal-weight concrete (NWC) and eight of ALWAC. ALWAC beams exhibited more extensive and wider flexural cracks compared to NWC beams under the same loading conditions. ALWAC beams demonstrated structural performance similar to NWC beams under identical loading conditions. The cracking loads of ALWAC can be estimated through measured concrete strength, with the post-cracking behavior predominantly influenced by the tensile reinforcement. All considered design codes underestimated the shear capacity of the tested ALWAC beams, and the shear resistance estimated by EC2 corresponded more closely than other existing codes. Lastly, the limitations and future work based on the results of this study were discussed and summarized.

Keywords

• shear capacity
• lightweight aggregate concrete
• reinforced concrete beam
• structural design