Abstract

In this study, the mechanical properties of an eco-friendly hemihydrate phosphogypsum-based composite (HPGC) added with basalt, glass, and PVA fibers upon exposure to high temperatures (250°C, 450°C, 650°C, and 850°C) were investigated. The fibers content (0%-1.35 vol%) did not have a significant effect on compressive strength at ambient temperature, while the flexural strength of HPGC was enhanced optimally at 1.0% fiber volume. For the investigation at high temperatures, the fiber inclusion could effectively reduce the cracks but increased the mass loss of HPGC. Compared to other fiber types, HPGC with PVA fiber, which did not melt at 250°C, exhibited the highest compressive strength and flexural strength (32.59 MPa and 10.56 MPa, respectively) at the temperature of 250°C but had a greater strength reduction between temperatures of 450°C and 850°C. At 850°C, HPGC with basalt fiber exhibited higher flexural strength than HPGC added with other fibers, and with 133.3% higher flexural strength than HPGC without fiber. The microstructural investigation confirmed that the changes of calcium sulfate forms (dihydrate to hemihydrate and anhydrite) and ettringite in the matrix contributed to the strength loss of all HPGC mixtures at high temperatures, while the existence of basalt fiber-matrix bond allows the HPGC added with basalt fibers to have the best residual properties at 850°C compared to the other mixes.

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 call

Disclaimer: 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.