Simulation of Fresh Concrete Flow

The vast family of industrial cementitious materials presents such a variety of behaviors in the fresh state that describing them as a whole seems unattainable (cf. Fig 1.1). This is even more so for our objective here: studying the possibility to predict their response in practical processing conditions.

The behaviour of fresh concrete during its mixing, transport, placement, and compaction can ultimately have significant effects on its mechanical performance, durability, surface appearance, and on its other properties after hardening. In concrete construction many problems result from the improper filling of formwork, insufficient de-airing, concrete segregation, etc. The importance of these issues has increased year after year since formwork is becoming continually more complex. Steel reinforcement has become denser, and the range of workability has been considerably broadened by the use of self-compacting concrete (SCC) and other novel concrete materials. Consequently, on the one hand, modern material design must match particular demands resulting from the geometrical and technological conditions to which the material is subjected. On the other hand, the concrete working techniques and, in some cases, the geometry of structures can be optimised in considering the usage of particular concretes with their special rheological properties. So, in order to build concrete structures efficiently and with high quality, the consistency of the fresh concrete should comply with the requirements posed by the structure’s geometry and by the methods of transport, placing, and compaction. Computer simulation of fresh concrete behaviour and the working processes could provide a powerful tool in optimising concrete construction and developing new concrete technologies [1].