Self-Consolidating concrete (SCC) is a high-performance concrete that can flow easily into tight and constricted spaces without segregating and without requiring vibration. The key to creating self-consolidating concrete (SCC), also referred to as self-compacting, self-leveling, or self-placing concrete, is a mixture that is fluid, but also, stable, to prevent segregation.
To achieve the desired flowability a new generation of superplasticizers based on polycarboxylate ethers works best. Developed in the 1990s, they produce better water reduction and slower slump loss than traditional superplasticizers. The required level of fluidity is greatly influenced by the particular application under consideration. Obviously the most congested structural members demand the highest fluidity. However, element shape, desired surface finish, and travel distance can also determine the required fluidity.
Generally, the higher the required flowability of the SCC mix, the higher the amount of fine material needed to produce a stable mixture. However, in some cases, a viscosity-modifying admixture (VMA) can be used instead of, or in combination with, an increased fine content to stabilize the concrete mixture. (information from the Portland Cement Association – www.cement.org)