Quantitative microstructural characterisation of cement paste submitted to different moderate temperature and loading conditions

The temperature is known to influence the strength and durability of concrete. Temperature has also a great influence on the creep of cementitious materials. Previous investigations have not provided a complete understanding of these effects; in particular, no quantitative relation between microstructural and macroscopic changes has been developed. In this paper, a combination of macro and micro characterisation has been adopted to further a comprehensive and quantitative understanding of the development of the mechanical and microstructural properties under different loading conditions and moderate temperatures (< 100°C). Different approaches including both qualitative and quantitative microstructural analysis with SEM, EDS, XRD and TGA were used. A study on different cement pastes has been carried out, to relate microstructural properties such as degree of hydration, CSH composition, relative density and capillary porosity to macroscopic observations. The chemistry of CSH is examined with temperature, the quantity of bound water for different curing conditions was investigated. © 2009 Taylor & Francis Group.