The IGF project 18936 N of VDZ gGmbH is supported by the AiF within the framework of Industrial Collective Research (IGF) of the Federal Ministry of Economic Affairs and Energy on the basis of a decision of the German Bundestag.
Investigations on the suitability of dolomitic carbonate rocks as cement main constituent
The aim of the planned research project is to investigate the suitability of dolomitic carbonate rocks as cement main constituent. Therefore, cement tests and systematic concrete and concrete durability tests are foreseen, based on several clinkers in combination with various dolomite-rich carbonate rocks. In the case of the carbonate rocks, the influence of rock-specific parameters, such as the geological origin and the height of the dolomite part, as well as the role of the dolomite in cement hydration, are to be clarified.
The dolomite-rich carbonate rocks (pure, marly, sandy or calcareous dolomites or dolomitic limestones) of different geological origin as well as the Portland cement clinkers with different mineralogy and fineness are characterized in detail by analytical methods. CEM II/A- and CEM II/B cements (with 20 and 30% by weight of carbonate constituent) and corresponding concretes will be prepared for the tests. Relevant cement and concrete properties are analyzed. The results serve to define requirements for dolomite-rich carbonate rocks as required for the production of high-performance dolomitic cements and durable concretes. In addition, it has to be clarified whether a dedolomitization takes place during cement hydration, and, if so, what is the impact on concrete properties.
On the basis of the research findings, small and medium-sized cement producers (SMEs) are given an improved assessment of the effects of the use of dolomite-rich carbonate rocks. In the medium term, the results are expected to contribute to the use of dolomite-containing carbonate rocks, with less than 75% by weight of calcium carbonate, as a cement main constituent. This helps the companies to withstand the increasing economic pressure in Germany.