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No-slump concrete (NSLC) and self-compacting concrete (SCC) are two types of concretes, which became increasingly adapted by the concrete industry because of their specific rheological characteristics. For NSLC mixtures the high shape holding ability allows formworks to be removed shortly after concrete placing. However, NSLC needs a large amount of energy to be properly compacted. For SCC mixtures it is the high flowability and self-compactability that makes them unique. However, as SCC is not able to preserve its shape right after placing, formwork cannot be removed directly after casting. By comparing these two extreme cases, an ideal mixture would have been obtained, i.e. a self-compacting no-slump concrete (SCNSLC), which can compact under its own weight and maintains its shape right after casting. in this paper the possibility of a self-compacting no-slump concrete (SCNSLC) is discussed. The rheological behaviour of these mixtures in the dormant period is in focus, when the degree of hydration is still very limited. The shape holding ability of both mixtures is characterized by a shape preservation factor 0

This paper provides results of an experimental study on the force-distance relationship between two particles connected by a liquid bridge. This experimental research is based on water bridges and extended to cement paste bridges with the aim to explain and model the rheological behaviour of fresh concrete mixtures, and to create a fundamental basis for developing mixtures with a predefined deformation performance. The research approach is based on a conceptual idea where the mixture is considered as an assembly of mutually interacting “particle-paste- particle” systems and the rheological behaviour of the mixture is related to the inter-particle interactions. The concept of capillary cohesion in wet granular materials, which describes the interaction between two particles connected by a liquid bridge, is considered the first step in the investigations. The effect of the wettability of the particles on the force-distance relation of two particles connected by a liquid bridge is studied. Static and/or quasi-static situations are in focus, i.e. where the cohesion dominates over other effects generated by the liquid, such as viscosity and lubrication. Tests were carried out using spherical stainless steel and glass particles and water was used as the liquid with a surface tension of ain=0.072 mN/mm. The contact angle between water and glass is about 15° while between water and stainless steel it is about 60°. It is found that the wettability of particles has a great influence on the force-distance relation of the interacting particles. Conclusion is drawn regarding the possibility to use the generated data as a basis for modelling the rheological behaviour of cement-based mixtures. [ABSTRACT FROM AUTHOR]