Abstract
In this study, we conducted an initial investigation of the post-fire mechanical properties of concrete reinforced with Spanish broom fibers. The mechanical properties were determined at room temperature, and the post-fire mechanical properties were determined at elevated temperature, so that the fire resistance of the concrete could be determined. Five mixtures were considered: three with differently treated Spanish broom fibers, a polypropylene fiber mixture, and a reference concrete mixture. The concrete and reinforced concrete samples were first dried to 100 °C, then heated to 400 °C, and left to cool to room temperature. The samples were tested immediately and 96 h after cooling. The compressive strength, weight loss, ultrasonic pulse velocity, and dynamic modulus of elasticity were determined and compared. The cross-sectional images of the concrete samples captured through an optical microscope were observed and analyzed. The changes in fiber structure were monitored by TG/DTG analysis. The results of the study indicate that even the reference concrete mixture did not have satisfactory residual properties. The reinforced concretes did not improve the residual properties of the reference concrete, but reduced the spalling and explosive failure performance under a compressive load. The concrete reinforced with Spanish broom fibers showed improved residual properties compared with concrete reinforced with polypropylene fibers.
Highlights
Concrete is a composite material that is widely used in buildings, industrial infrastructure, and other applications around the world
The mechanism of polypropylene fibers when exposed to high temperatures is the most efficient amongst those of synthetic fibers because they melt at 170 ◦ C and create a porous structure, which reduces the build-up of pore pressure inside the heated concrete structure [9]
The results showed that the addition of coconut fibers improved the strength and fire resistance of the concrete, performing even better than polypropylene fibers
Summary
Concrete is a composite material that is widely used in buildings, industrial infrastructure, and other applications around the world. The mechanism of polypropylene fibers when exposed to high temperatures is the most efficient amongst those of synthetic fibers because they melt at 170 ◦ C and create a porous structure, which reduces the build-up of pore pressure inside the heated concrete structure [9] They perform better than steel fibers in preventing spalling, they negatively affect the concrete’s other mechanical properties, since they reduce the remaining compressive strength, modulus of elasticity, and tensile strength of the fired concrete [4,10]. The results showed the better performance of banana-fiber-reinforced concrete in terms of losses in compressive strength over plain and other concrete samples after exposure to 200 and 400 ◦ C They concluded that the fire resistance of banana-fiber-reinforced concrete can be improved by partially replacing cement with fly ash. This is an initial study of concrete reinforced with Spanish broom fibers and it shows a guideline in which further investigations can be obtained
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
