Effect of micro-silica on the physical, tensile, and load-deflection characteristics of micro fiber-reinforced high-performance concrete (HPC)

• Published in: Case Studies in Construction Materials 2022-12, Vol.17, p.e01380, Article e01380
• Main Authors: Raza, Syed Safdar, Amir, Muhammad Talha, Azab, Marc, Ali, Babar, Abdallah, Mirvat, El Ouni, Mohamed Hechmi, Elhag, Ahmed Babeker
• Format: Article
• Language: English
• Subjects: Flexural toughness; Load-deflection behavior; Micro-carbon fiber; Micro-silica; Tensile strength; Ultrasonic pulse velocity
• ISSN: 2214-5095; 2214-5095
• DOI: 10.1016/j.cscm.2022.e01380

In this research, the influence of micro-silica (MS) was studied on the tensile and flexural behavior of micro-carbon fiber (MCF) reinforced HPC. For this purpose, a total of twelve concrete mixes were designed incorporating six different doses of MCF (at 0%, 0.15%, 0.25%, 0.5%, 0.75% and 1%) with and without MS.The examined properties included compressive strength, splitting tensile strength, load-deflection behavior, ultrasonic pulse velocity, and water absorption. It was found that without MS inclusion, MCF shows a nominal contribution to the mechanical properties. However, the efficiency of MCF incorporation improved phenomenally due to MS addition. The incorporation of MCF at an optimum dose (0.5–0.75% volume fraction) showed 32% and 6% net improvements in modulus of rupture with and without MS, respectively. The micro-filler and pozzolanic effect of MS particles enhanced the bond strength and efficiency of micro-filaments of MCF. MS incorporation delayed the fracture of fiber-reinforced HPC under flexural loading.