Quantification of the strength forming-phase in cementitious materials (C-S-H)

• Applicants: Professor Dr. Jürgen Neubauer; Professor Dr.-Ing. Frank Schmidt-Döhl
• Subject Area: Construction Material Sciences, Chemistry, Building Physics
• Term: from 2015 to 2019
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 280067300

Aim of the research project is the development of an analysis method to quantitatively determine the concentration of the calcium-silicate-hydrate-phase (C-S-H-phase) of mineral building materials. The C-S-H-phase is the strength-forming phase of cementitious materials as concrete and many mortars. Due to the importance of these materials one can say that our built environment to a large extent is based on C-S-H. The quantitative analysis of this phase is up to now restricted to strongly simplified model systems. The possibility to quantitatively analyze this phase in real materials is of great importance for the optimization of building materials, as well as for the assessments of damage processes. Within the project an analysis method based on ATR-FT infrared spectroscopy is supposed to be developed. The preliminary investigations lead to the hypothesis that with the planned methodology any cement paste, as well as concrete and mortar with quartz as aggregate, can be analyzed without extensive pretreatment. In this way real concrete and mortar whose C-S-H-phase can be analyzed quantitatively are producible in the laboratory. In the construction practice concrete contains also many other mineral in the aggregate. This makes it necessarily to separate aggregate and binder as an additional preparation step before the analysis. Methodology and limiting conditions of the analysis procedure are supposed to be examined within the project in detail.

• DFG Programme: Research Grants