Journal
CONSTRUCTION AND BUILDING MATERIALS
Volume 226, Issue -, Pages 11-20Publisher
ELSEVIER SCI LTD
DOI: 10.1016/j.conbuildmat.2019.07.289
Keywords
Phosphorus building gypsum; Calcium sulfoaluminate cement; Ground granulated blast furnace slag; Self-leveling mortar; 30-Min slump loss; 1-day strength
Categories
Funding
- National Natural Science Foundation of China [51822807]
Ask authors/readers for more resources
Due to the higher 30-min slump loss and the lower 1-day strength of phosphorus building gypsum (PBG), its use for gypsum-based self-leveling mortar is limited, which makes its recycling low value-added and ineffective. In this work, PBG is modified by adding calcium sulfoaluminate cement 42.5R (S) and three types of ground granulated blast furnace slags (GGBSs), which are ordinary GGBS (OG, d(50) = 11.3 mu m), ultrafine GGBS A (UA, d(50) = 3.67 mu m) and ultrafine GGBS B (UB, d(50) = 2.65 mu m), to prepare PBG-based self-leveling mortar (PSLM). When adding S alone, the 30-min slump loss and 1-day strength of PSLM are the highest. GGBS replacing S can decrease 30-min slump loss and 1-day strength. The 30-min slump loss decreases with smaller GGBS particle size. The increase in hydration degree caused by the decrease in GGBS particle size does not cause an obviously negative effect on the slump of PSLM. UA and UB can reduce 30-min slump loss to less than 3 mm by decreasing plastic viscosity growth and yield stress. When the mix proportion of S and GGBS is optimum, the hydration reactions of S and GGBS promote each other, which ensures the higher 1-day strength. The hydration degrees increase, the microstructure becomes denser, and the 1-day strength increases with smaller GGBS particle size is. A novel PSLM with good performances meeting the requirements of JC/T 1023-2007 (Gypsum-based self-leveling floor compound) can be prepared by adding S and UA/UB, which is beneficial for the comprehensive utilization of phosphogypsum. (C) 2019 Elsevier Ltd. All rights reserved.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available