Hydration Mechanism and Durability of Calcined Phosphogypsum Slag Cement Concrete
LIAO Yishun
JIA Xiqiang
WAN Shihui
CAI Zhonghui
LIU Jia
Abstract：Through tests on hydration heat,electrical resistivity,pH value of pore solution,compressive and flexural strength,softening coefficient and electric flux,along with X-ray diffractometer and scanning electronic microscope analyses,the hydration process,water resistance and chloride penetration resistance of phosphogypsum slag cement concrete were studied.The results show that with the increase of calcined phosphogypsum(CPG)content,the hydration heat and electrical resistivity of cement paste at 3 days increase gradually,and the main hydration products are gypsum and ettringite(AFt).When the CPG content increases from 40%to 70%,the 28-day compressive and flexural strength of concrete decrease by 28.3%and 30.0%,respectively.The pH value of the pore solution remains basically unchanged,the AFt content decreases from 27.6%to 8.0%.The softening coefficients of CPG slag cement concrete specimens are greater than 1,the electric fluxes are less than 500 C,indicating that the concrete has very good water resistance and chloride penetration resistance.
Keywords：calcined phosphogypsum slag cement concretehydration heatelectrical resistivitychloride ion permeability
Publication Date：2025-05-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 425-433 )