The 4th Asian Concrete Federation Symposium on Emerging Technologies for Structural Longevity (ACF2023- ETSL)

4 / 2022-02-24 15:21:30

Research on the effect of basalt fiber on physical and mechanical properties and microstructure of white silicate cement

Basalt fiber；,Mechanical properties,Electromagnetic properties,Microscopic morphology,Pore characteristics

This paper investigated the effect of basalt fibers on the physical and mechanical properties of white silicate cement paste. Five groups of cement pastes with different basalt fiber admixtures were investigated for their mechanical and electromagnetic properties as well as microstructure. To determine the alkali resistance of basalt fibers, the fibers were immersed in saturated Ca(OH)₂ solution for 3 d and 28 d, and the microscopic morphology and composition of the fibers after corrosion were analyzed. The results showed that: basalt fibers reduced the fluidity of cement paste, but increased the strength of cement paste; white crystals were generated on the surface of fibers after 28d immersion in saturated Ca(OH)₂ solution, and the generated substance was identified as CaCO₃ by combining with X-ray diffraction (XRD) analysis; fibers were tightly bonded to the cement matrix, and the Si and Al elements contained in the fibers decreased after the reaction with cement solution The content of Si and Al elements contained in the fibers decreases after reacting with the cement solution; the addition of fibers increases the porosity of the cement paste and refines the pore structure characteristics; with the increase of basalt fiber admixture, the dielectric constant of the cement paste decreases and the electromagnetic transmission properties are improved.