Quantifying Embodied Carbon Impacts of Construction Disputes in Offshore Platform Building: A Tiered LCA Model

Construction disputes represent a significant yet overlooked source of embodied carbon in offshore platform projects. Existing LCA frameworks grounded in ISO 14040/14044 define system boundaries around planned resource consumption, but rarely account for incidental disruptions such as work stoppages and rework triggered by conflicts. This study introduces a novel tiered LCA model that quantifies dispute-induced embodied CO2e surges during the construction phase by tracking three carbon sources: raw materials, machinery, and labor. Disputes are classified as mild (<1 week), moderate (1–12 weeks), and severe (>3 months) based on empirical literature, with escalating impacts from labor idleness to material degradation and comprehensive reconstruction. Applied to a South China Sea semi-submersible rig case study (35,000 t steel, ~395,000 t CO2e baseline using provisional parameters comparable to the Haiyang Shiyou 981), results show that mild disputes add ~12 t CO2e from idle labor, moderate ones ~1230 t CO2e from partial rework (1% extra steel), and severe ones ~11,220 t CO2e from full reconstruction (10% extra steel). The step-function escalation—driven by marine corrosion thresholds crossing from labor-only to material-intensive penalties—demonstrates that dispute carbon is a latent environmental cost. By bridging conflict management and LCA, the model validates the feasibility of embedding dispute-carbon tracking into BIM-LCA platforms to visualize and proactively mitigate delay-related emissions.