Life Cycle Assessment of Reinforced Concrete Beam Work for Environmental Hotspot Identification and Mitigation

Abstract

Reinforced concrete structural work requires substantial materials, energy, and transportation, which may generate environmental burdens throughout construction-related processes. This study identifies environmental hotspots in reinforced-concrete beam work and establishes mitigation priorities using Life Cycle Assessment (LCA). A case study was conducted on Project X in Magelang Regency by aggregating two beam groups into one beam-work system comprising 1,935.78 kg of reinforcing steel, 42.805 m² of formwork, and 4.290 m³ of ready-mix concrete. The functional unit was defined as 1 m³ of installed reinforced-concrete beam work, while the system boundary covered material production, transportation to the construction site, and construction activities. Modelling used SimaPro-derived inventory data and ecoinvent datasets with ReCiPe 2008 Midpoint (H) v1.13. The climate-change impact was approximately 5.62 × 10³ kg CO₂ eq, equivalent to about 1.31 × 10³ kg CO₂ eq/m³. Reinforcing steel was the principal hotspot, contributing approximately 69.6%, followed by cement at 21.5% and plywood at 4.3%. Sensitivity analyses of concrete composition, steel representation, formwork reuse, and transportation confirmed that reinforcing steel remained the dominant hotspot. Literature-based validation indicates that mitigation should prioritize reinforcement efficiency, fabrication-waste reduction, lower-impact steel procurement, cement efficiency, formwork reuse, and logistics optimization.