Fibre Reinforced Concrete: from sustainable LC3-based strain-hardening composites to FRC design...

Theme of the RYC/fib YMG Peer-to-Peer Webinar: Fibre Reinforced Concrete: from sustainable LC3-based strain-hardening composites to FRC design provisions & quality control Hosts: Dr Niki Trochoutsou, RILEM Youth Council Chair and Dr Thilo Schmidt, fib Young Member Speaker: Ameer Hamza Ahmed, Institute of Construction Materials, TU Dresden & Cluster of Excellence CARE, TU Dresden and RWTH Aachen, Germany Title: Elucidating the role of enforced carbonation and clinker reduction in PET fiber-reinforced strain-hardening cementitious composites (SHCC) Strain-hardening cementitious composites (SHCC) are known for their superior tensile ductility and crack-control performance, making them highly attractive for strengthening, repair, and retrofitting applications. However, conventional SHCC formulations rely on high clinker content, significantly increasing their environmental footprint. Compounding this, the most commonly used fibers, PVA and PE, are costly and raise sustainability concerns. While PET fibers offer an excellent, low-cost, and recyclable alternative, their susceptibility to degradation in highly alkaline cementitious environments has long limited their practical use. This work addresses both challenges simultaneously. By combining low-clinker LC3 binders with enforced carbonation, it is possible to lower matrix alkalinity, protect alkali-sensitive PET fibers, and sequester CO2, all while maintaining excellent mechanical and durability performance. Beyond PET, this strategy opens the door to a broader class of sustainable, alkali-sensitive fibers whose potential has been constrained by similar durability concerns – redefining how CO2 utilization and binder design can together unlock truly sustainable fiber-reinforced composites. ABOUT RILEM: The mission of RILEM is to advance scientific knowledge related to construction materials, systems and structures and to encourage transfer and application of this knowledge world-wide. This mission is achieved through collaboration of leading experts in construction practice and science including academics, researchers, testing laboratories and authorities.