Ultra-high-performance fiber-reinforced concrete for sustainable and resilient infrastructure a state-of-the-art review

Ultra-High-Performance Fiber Reinforced Concretes (UHPFRCs) have evolved into one of the most sophisticated cementitious composite technologies to develop highly durable, resilient and sustainable infrastructures. While there is an abundance of research available on UHPFRC, many of the existing review studies typically focus on sustainable materials, fiber reinforcement techniques, mechanical properties, durability, and/or infrastructure applications individually. Therefore, a holistic approach to connect all of these individual areas remains somewhat limited. This review assesses recent developments in UHPFRC using a systematic evaluation of sustainable constituents, fiber reinforcements, mechanical properties, durability aspects, infrastructure applications, and sustainability. The review was developed based on five research questions focused on sustainable material development; fiber reinforcement mechanisms; long term durability; infrastructure implementation; and future research priorities. Based on the findings presented in this review, it is demonstrated that the use of supplementary cementitious materials, recycled materials and improved particle packing arrangements can provide substantial improvements in the sustainability of UHPFRC without compromising its excellent structural engineering performance. The role of fiber reinforcement systems is paramount in determining tensile strength, strain hardening behavior, fracture toughness and ability to resist cracking. In addition to demonstrating the significant durability of UHPFRC, which includes its high resistance to chloride penetration, corrosion, freeze–thaw damage, sulfate attack and environmental degradation, will contribute to extended service lives and increased resilience in infrastructures. The use of UHPFRC in bridge engineering, marine structures, protective systems, seismic resistance systems and rehabilitation systems demonstrate the applicability of UHPFRC in harsh environment conditions. Additionally, from a sustainability viewpoint, life cycle assessments show that despite higher environmental impacts in the construction process of UHPFRC due to higher cost and energy usage, the reduced need for repairs and replacement over time results in a reduction in overall environmental impacts and resource utilization. As such this review defines several major obstacles to widespread acceptance including high production costs, fire induced spallation, lack of long-term field-testing data and lack of widely recognized performance-based design criteria. By unifying materials science approaches to develop sustainable materials, fiber reinforcement technologies to enhance durability, applications to create new types of sustainable and resilient infrastructures and assessment tools to evaluate sustainability of new and existing systems, this review provides a holistic view of the current state-of-the-art of UHPFRC technology as well as identifies essential research priorities for creating sustainable and resilient systems for future generations.