Environmental performance of sustainable supersulfated cements based on blast furnace slag: A life cycle study

This study evaluates the environmental, economic, and mechanical performance of supersulfated cements (SSC) made with blast furnace slag (BFS) as a low-carbon alternative to Portland cement (PC). It combines Taguchi optimization and life cycle assessment (LCA) to examine the effects of slag fineness, curing conditions, and BFS allocation methods (mass, economic, and no allocation) on three previously optimized SSC compositions. Two scenarios representing different plant locations, were considered. This study presents three major contribution: (1) a quantified framework for balancing mechanical performance and sustainability, with optimized SSC formulations achieving 28-day compressive strengths ≥32.8 MPa under controlled curing conditions; (2) a comprehensive LCA demonstrating CO₂ reductions of at least 89 %, 83 %, and 47 % depending on the allocation method, positioning the SSC as a building material with very low climate impact; and (3) a detailed cost analysis showing up to 73 % savings compared to PC, reinforcing the economic viability of SSC for real-world applications. These findings highlight the SSC role in decarbonizing the construction sector, aligning with Sustainable Development Goals on climate action, circular economy strategies, and resilient infrastructure.