Effect and Mechanism of Shrinkage Reducing Admixture on Alkali-Activated Slag-Copper Slag Mortar
XU Rongsheng
WANG Haoran
YANG Renhe
KONG Fanhui
HONG Tong
Abstract：The volume stability of alkali-activated slag-copper slag mortar(CSM)was improved by incorporating polyether-type shrinkage reducing admixture(PSRA).The effects of PSRA content on the setting time,compressive strength and drying shrinkage of CSM were investigated.The hydration process and microstructure of CSM were studied by isothermal calorimetry,X-ray diffractometer,scanning electron microscopy-energy dispersive spectrometer,nuclear magnetic resonance and thermogravimetric-differential scanning calorimetry.The shrinkage reduction mechanism of SRA was explored.The results show that the incorporation of PSRA extends the setting time of CSM slurry,and delays the hydration process of the system,with the delaying effect increasing as the PSRA content increases.When the PSRA content ranges from 0%to 2.0%,both the drying shrinkage and compressive strength of CSM gradually decrease with the increase of PSRA content.PSRA reduces the surface tension of the pore solution and changes the pore structure,resulting in a decrease in capillary pressure and thus reducing drying shrinkage of CSM.
Keywords：alkali-activated slag-copper slag mortarpolyether-type shrinkage reducing admixturedrying shrinkagecompressive strengthmicrostructure
Publication Date：2024-11-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：7( 1047-1053 )