With the rapid development of the engineering industry

the demand for traditional concrete materials has been steadily increasing

prompting researchers to explore new alternative materials. Industrial by-products such as red mud are believed to have potential in resource conservation

cost reduction

and mitigating environmental impact. However

the hydration mechanism of these solid waste materials in cementitious materials remain unclear. In this study

comprehensive analysis of the hydration kinetics of cementitious materials containing red mud

steel slag

fly ash

and phosphogypsum was conducted using low-field nuclear magnetic resonance and isothermal calorimetry. The study indicates that the hydration process of red mud-based cementitious materials can be divided into three stages: nucleation and crystallization

phase boundary reactions

and diffusion

with the reaction rate being highest during the nucleation and crystallization stage. Steel slag and phosphogypsum accelerate the hydration reaction and improve the material’s pore structure

while fly ash

although reacting more slowly

also contributes to the eventual improvement of the pore structure. Statistical results show that early hydration heat release is strongly correlated with the compressive strength at 7 days

which can effectively predict the material’s early strength.