Comparison of moisture equilibrium of cement-based materials in presence of slag and silica fume in different wetting and drying cycles
Författare
Summary, in English
Water vapor sorption isotherms are essential data in models to predict the service life of the cement based structures. The knowledge about sorption isotherms in the presence of supplementary cementitous materials (SCMs) is limited. This study investigates the influence of water to cement ratio (0.4, 0.5 and 0.6), and the presence of two SCMs (70% slag and 10% silica fume) on sorption isotherm in hygroscopic and above hygroscope RH ranges for paste and mortars. Dynamic vapor balance in hygroscopic rang and pressure plates above hygroscopic range are used to generate sorption isotherms. Based on Jennings model (CM-II) for C-S-H structure, desorption isotherms are divided to different parts in which different pores are emptied. The samples with silica fume and slag have higher moisture content than OPC, but, with higher amount of gel pores and lower amount of capillary pores. At low RH intervals all samples have very similar desorption curves and introduction of SCMs induce slightly increase on BET surface area. Above 30% RH, samples have different desorption curves and the initial desorption is higher than following desorption for all samples.
Avdelning/ar
Publiceringsår
2014
Språk
Engelska
Sidor
813-818
Publikation/Tidskrift/Serie
Proceedings of the First International Conference on Construction Materials and Structures
Dokumenttyp
Konferensbidrag
Förlag
IOS Press
Ämne
- Construction Management
Nyckelord
- Water vapor sorption isotherms
- supplementary cementitous materials
Conference name
1st International Conference on Construction Materials and Structures
Conference date
2014-11-24 - 2014-11-26
Conference place
Johannesburg, South Africa
Status
Published
ISBN/ISSN/Övrigt
- ISBN: 978-1-61499-466-4
- ISBN: 978-1-61499-465-7