Cutting Waste Minimization of Rebar for Sustainable Structural Work: A Systematic Literature Review

Keehoon Kwon,Doyeong Kim,Sunkuk Kim

doi:10.3390/su13115929

Abstract

Rebar, the core resource of reinforced concrete structures, generates more carbon dioxide per unit weight than any other construction resource. Therefore, reducing rebar cutting wastes greatly contributes to the reduction of greenhouse gas (GHG). Over the past decades, many studies have been conducted to minimize cutting wastes, and various optimization algorithms have been proposed. However, the reality is that about 3 to 5% of cutting wastes are still generated. In this paper, the trends in the research on cutting waste minimization (CWM) of rebar for sustainable work are reviewed in a systematic method with meta-analysis. So far, the literature related to cutting waste minimization or optimization of rebar published has been identified, screened, and selected for eligibility by Preferred Reporting Items for Systematic Reviews and Meta-Analyses, and the final 52 records have been included in quantitative and qualitative syntheses. Review by meta-analysis was conducted on selected literatures, and the results were discussed. The findings identified after reviewing the literature are: (1) many studies have performed optimization for the market length, making it difficult to realize near-zero cutting wastes; (2) to achieve near-zero cutting wastes, rebars must be matched to a specific length by partially adjusting the lap splice position (LSP); (3) CWM is not a one-dimensional problem but an n-dimensional cutting stock problem when considering several rebar combination conditions; and (4) CWM should be dealt with in terms of sustainable value chain management in terms of GHG contributions.

Highlights

Google Scholar has confirmed that it includes various reports such as books, content, and dissertations along with academic papers in most databases, as shown in Scholar was used to search for books, magazines, and documents such as dissertations, which are not well searched for in databases such as Web of Sciences (WoS) and American Society of Civil Engineers (ASCE), and when original text could be downloaded from these databases
The number of literatures corresponding to rebar cutting optimization through the identification, screening, and eligibility process was a total of 403, and 52 literatures related to Reinforced concrete (RC) design optimization were selected, excluding 351 literatures that fall under the category of pre-processing research of rebar optimization. They address the problems of rebars cutting waste, corresponding to post-processing research of rebars optimization after RC design. These literatures will be reviewed by factors such as application of optimization techniques and graphic solutions for cutting waste minimization (CWM), range of rebar work process, consideration of lap space position, reflection of length in a special order, consideration of bending margin, and consideration of schedule
Several facts have been identified in addition to findings identified from meta-analysis, as described in the Section 3

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Reinforced concrete (RC) structures, such as buildings and infrastructure, use enormous amounts of concrete and rebar during the construction phase. In 2012, global concrete and concrete constituent consumption reached about 10 billion m3 [1], and the amount is rapidly increasing every year due to increased demand for RC structures along with global economic development. The core resource of RC structures, generates more CO2 per unit weight than any other construction resource. C25/30 concrete generates embodied CO2 (ECO2 ) of 95 kg-ECO2 /t, but reinforcement bar (rebar) generates ECO2 of

Methods

Results

Conclusion