The main purpose of the thesis was study of influence of chemical admixtures and mineral additives on the rheological properties of fresh cement mortar, so called CEM mortar. Composition of particular mortar mixture was determined from composition of relevant concrete mixture, by concrete equivalent mortar method (CEM method).
All the measurements were performed in laboratory of the Faculty of Civil and Geodetic Engineering of University of Ljubljana. The rheological parameters were measured using a
rheometer ConTec Viscometer 5 and by parallel measurements of mortar flow value on flow table. Research on the concrete, comparison between concrete and mortar mixtures and evaluation of CEM method were carried out within the thesis and doctoral dissertation. 26 different mortar compositions, which can be classified into 8 groups, were mixed and tested. All mixtures contained aggregate, cement and water. The mixtures differ by the content of chemical admixtures and mineral additives, type of cement and water to cement ratio. Mineral additives, which replaced part of the cement, were microsilica, tuff and ground granulated blast furnace slag. Chemical admixtures used in the study were superplasticizer and air entraining agent. We used also two different type of cement. Test results are presented in reographs and graphs that show relationship between yield value or flow value and content of studied mortar constituent. The tests were carried out immediately after the mixing of mortar was completed and 20 min, 40 min and 60 min after the mixing completion.