Green and low-carbon matrices for Engineered/Strain-Hardening Cementitious Composites (ECC/SHCC): Toward sustainable and resilient infrastructure

Engineered/Strain-Hardening Cementitious Composites (ECC/SHCC) are the most concerned high-performance fiber-reinforced cementitious composites in recent years. Well-known for their high/ultra-high deformation capacity (typically 3-10%) and distinguished crack width control ability under tension, ECC/SHCC demonstrate significant potential for use in resilient infrastructure applications. Incorporating industrial/agricultural/urban wastes/by-products into ECC production offers a compelling and sustainable approach to upcycle these materials, resulting in green and cheap ECC production. This study critically reviews the utilization of wastes/byproducts as green and low-carbon matrix materials (including binders and aggregates) to enhance the overall sustainability of Portland cement-based ECC. The analysis encompasses their mechanical, durability, and environmental performances based on existing literature. Notably, sustainable binders are primarily prone to influence the fracture toughness of matrices and the fiber/matrix chemical/frictional bond, while sustainable aggregates tend to affect the fracture toughness of matrices, fiber orientation and distribution, fiber/matrix frictional bond, and aggregate/matrix interfacial bond. The findings underscore the practical applicability of ECC with sustainable matrices in infrastructure, supporting practitioners and policymakers in adopting materials that meet durability and environmental goals. This work concludes by presenting perspectives and recommendations for future studies, focusing on the use of low-carbon and sustainable matrices in ECC materials for greener and more resilient infrastructure.