Combined mechanical couplers and special-length-priority algorithm for reducing rebar consumption and cutting waste of beam reinforcement

Abstract

The surging demand for reinforced concrete buildings has led to excessive consumption of rebars, resulting in substantial rebar-cutting waste and greenhouse gas emissions. Various approaches have been explored to mitigate this issue, including lap-splice optimization and the use of special-length rebars without adhering to lapping zone rules. However, these methods do not adequately address rebar overconsumption. Conventional lap splicing is associated with several drawbacks, such as excessive rebar consumption and structural integrity concerns. Therefore, mechanical couplers have emerged as promising alternatives to address these limitations. This study assessed the impact of a combined coupler and special-length-priority optimization algorithm on reducing rebar consumption and cutting waste in beams, with the aim of achieving near-zero cutting waste. The proposed algorithm was then applied to the reinforcement of beams in a high-rise building, and a significant reduction in ordered rebar consumption was achieved, reaching 17.28 % and 5.66 %, respectively, compared with the original design and a previous study. This reduction consequently lowered greenhouse gas emissions by 14.52 % and 2.51 % compared with the original design and previous study, respectively. Additionally, 12.98 % and 0.57 % reductions in the total cost were achieved compared with the original design and previous study, respectively. The results of this study offer a novel perspective for the industry to further minimize rebar consumption and its associated sustainability implications without compromising structural integrity.