The 6th International Conference on Material Strength and Applied Mechanics
(MSAM 2023)

Abstract: The fiber reinforced cement slabs are non-load-bearing insulating products, in which cement could be replaced for carbon reduction. Phosphogypsum (PG) is an industrial by-product gypsum obtained from wet process production of phosphoric acid, and it is one of the largest solid waste emissions in the chemical industry. First, we prepared the modified phosphogypsum slag (MPS) with phosphogypsum, cement, and slag powder. Then the content of solid waste phosphogypsum with 10%, 20%, 30% and 40% in fiber reinforced cement slab was tested. When MPS was mixed at 30% of the cement mass, the strength of the specimens at all ages still meet the requirements, thus achieving the best balance between solid waste utilization and performance requirements. In addition, glass beads and POM fibers were also considered to improve the mechanical property of fiber reinforced cement slabs. The CT scanning and X-ray test results showed there was good bonding between the POM fibers and the phosphogypsum slag-cement mortar matrix. The hollow glass beads were evenly distributed in the matrix, filling the pores, and there was no agglomerative consolidation, which greatly improved the microscopic pore characteristics and helped to improve the crack resistance and ductility of the material. Also, a 3D finite element model containing POM fibers and hollow glass microbeads was built to analyze the micro property. The ductility of the specimens increases with the addition of HGM.This indicates that the addition of HGM can significantly improve the resistance of the specimens to freeze-thaw damage. This study can provide a reference for the basic mechanical properties of modified phosphogypsum-hollow glass beads-fiber cement matrix composites.

Keywords: Fiber-reinforced cement slab, Modified phosphogypsum slag, Hollow glass beads, Freeze-thaw cycle, Flexural strength.

Biography: Dr. Jun Fu is a full professor from the Department of Harbor & Structure, Wuhan University of Technology (WUT), China. He was a visiting scholar at the University of Colorado (Boulder), USA from 2012-2013. His main research interests are light Ultra-High Performance Concrete & Steel structure, Multiscale modeling for cement-based structure & material, Solid waste phosphogypsum & cement-based material and service performance assessment and prediction for infrastructure structure & materials.