Dynamic mode rheology of cement and tricalcium silicate pastes from mixingto setting

Dynamic mode rheometry was used to study the evolution of the structure of cement and pure tricalcium silicate pastes from mixing up to setting and ev en after setting, together with the nature of the forces responsible for th e mechanical properties of the pastes. A special mixer-type tool was used t o study theology during the very first minutes following the end of mixing, which are out of reach with classical tools. Both kinds of pastes have the same behavior. It was found that the main evolution of the structure of th e pastes occurs during the very first minutes following the end of mixing, while there is no change in interparticular forces up to setting and even a few hours later. Setting, as defined by the Vicat needle, is not related t o any particular change of the nature of the forces or structural transitio n within the paste. (C) 2001 Elsevier Science Ltd. All rights reserved.