54 Summary In this experimental study, selected Devonian limestones of the Prague Basin (i.e. samples from the historic quarry of Branické skály) were examined to find their suitability for production of hydraulic limes or for natural cement. Four representative samples of the dvorecko-prokopské limestone were sampled in the form of blocks weighing approximately 10 kg each, from the layer of the quarry wall that had been chosen based on literature research. A detailed mineralogical-petrographic examination of samples was the first step, in an attempt to obtain their mineralogical composition, microstructure and texture. Samples were analysed by polarizing microscopy and cathodoluminescence of thin sections, and X-ray diffraction of insoluble residues determined by treatment with both the hydrochloric acid and the acetic acid solution. Mineralogical composition of the insoluble residuals was illite, kaolinite, quartz and Na-plagioclase (albite). Two samples contained among above mentioned mineral phases also chlorite. The utility of studied limestones for the production of hydraulic binders (hydraulic limes and natural cement) was derived from both the calculations based on obtained chemical analyses (included standard cement and lime indexes and modules) and the firing experiments. The firing experiments...

No / Hydration of five Roman and American natural cements was analyzed using X-ray diffraction, mercury intrusion porosimetry, and scanning electron microscopy of cement pastes. Two cements were prepared in the laboratory by burning marls from geological sources in Poland (Folwark) and Austria (Lilienfeld). The selection of raw materials and burning conditions were optimized so that the hydraulic nature and appearance of the final burnt materials matched as closely as possible historic Roman cements widely used in the 19th and the beginning of the 20th centuries in Europe to decorate buildings. Three other cements are produced commercially: quick setting Prompt cement from Vicat, France, and Rosendale cements from Edison Coatings Inc., USA. The hydration of the cements studied was shown to comprise two distinct stages. The immediate setting and early strength is due to the formation of calcium aluminum oxide carbonate (or sulfate) hydroxide hydrates. The development of long-term strength is brought about by the formation of calcium silicate hydrates. Similarities and differences between the individual cements are discussed.

Natural hydraulic lime and natural cement have been used in the building industry for centuries. These inorganic hydraulic binders are called "traditional" or "alternative" because they can, in some cases, substitute modern Portland cement. The recent increased interest in these binders is due not only to their use in restoration practices, but also because their production and use is less energetically demanding than in modern cements. Historically, many types of hydraulic binders were produced in the regions of Bohemia and Moravia. However, much information has been lost about their manufacturing process, which raw materials were used, and we are uncertain of the exact character and properties of the burned material. To date, studies have only addressed the impact of the chemical composition of raw material on the parameters of the burned material - all this is well known for Portland cement, much less for other types of hydraulic binders. The aim of this dissertation was to study the various types of raw materials (limestone containing non- carbon admixtures) and to understand the characteristics of their respective hydraulic lime and natural cement. This was done by analyzing the impact of conditions (highest achieved burning temperature and time of burning) and the mineral and chemical...