Magnesium induced hydration kinetics of ultra-high performance concrete (UHPC) served in marine environment: Experiments and modelling

摘要

In this study, magnesium induced hydration kinetics of ultra-high performance concrete (UHPC) served in marine environment are studied based on practical experiments and modelling. XRD quantitative analysis and TG-DSC test are employed to clarify the impact of magnesium ions on cement hydration. GEMS modelling is used to verify the influence of magnesium ions on cement hydration. The obtained results reveal that magnesium delays formation of AFt, Ca(OH)(2) and decomposition of Friedel's salt during early age. The influence of magnesium during early ages can be equivalent to decrease on specific area of cement based on modelling. In later age, magnesium induces accelerated cement hydration and promoted generations on AFt, Ca(OH)(2). Supposing that the inhibition and acceleration effect is brought by formation of magnesium corrosion products, mathematical analysis model on behaviors of magnesium corrosion products in UHPC system is developed. (C) 2019 Elsevier Ltd. All rights reserved.