Physical and mechanical properties of gypsum-based composites reinforced with basalt, glass, and PVA fibers

Abstract

The purpose of this experiment is to investigate the influence of basalt fibers (BF), glass fibers (GF), and Polyvinyl alcohol (PVA) fibers on the properties of fiber-reinforced gypsum-based composites including setting time, extended diameter, water absorption, and flexural strength. In this study, the change of experimental results was obtained by selecting the fiber type, length, volume, and surface treatment as influencing factors; the mechanisms of change in the context of existing research was explained. Moreover, the scanning electron microscope was further analyzed, and analysis models of different factors on the fiber reinforced gypsum matrix were depicted. The results indicated that, with the increase in fiber length and volume, the setting time and fluidity will decrease and water absorption will increase. Compared with control group, the optimal ratios of three selected fibers were all 10 mm and 1.0%; in addition, the flexural strength can be increased by more than 50%. Moreover, the setting time, fluidity, and water absorption can increase by HCl, NaOH, and KH550 silane coupling agent treatments on the BF surface, with an improvement effect within 5%. The HCl and NaOH treatments can form pit etching on the fiber surface through an oxide reaction, while a hairy transmission stress interface layer between the BF and gypsum can be formed by the KH550 silane coupling agent treatment, where the strength lifting effect is better.