Abstract
In response to growing environmental concern and the demand for high-performance sustainable materials in construction, this study explores the development of a sustainable ultra-high strength engineered cementitious composite (UHS-ECC) through the incorporation of recycled concrete powder (RCP) as a partial cement replacement and waste tire steel fiber (WTSF) as reinforcement. These materials, sourced from construction and industrial waste, aim to reduce the environmental footprint of cementitious composite while maintaining superior mechanical properties. A comprehensive life cycle assessment (LCA) was conducted, evaluating 18 major components, with a focus on the key impact categories including climate change potential, fossil depletion, human toxicity, and particular matter formation. Experimentally, the UHS-ECC achieved a maximum compressive strength of 129 MPa at a 5% RCP replacement level, with a gradual decline observed at higher substitution rates. The LCA results demonstrated significant reductions in environmental impacts, with up to 16% reduction in climate change potential (GWP20) and 19% reduction in fossil resource depletion when substituting cement with RCP, compared to conventional ECC. These findings underscore the potential of RCP and WTSF as viable sustainable alternative in high-strength composite production.