SCC Self Compacting Concrete

SCC Definition:

Self Compacting Concrete is an innovative concrete that does not require vibration for placing and compaction. It is able to flow under its own weight, completely filling formwork and achieving full compaction, even in the presence of congested reinforcement.

The hardened concrete is dense, homogeneous and has the same engineering properties and durability as traditional vibrated concrete.

SCC Potentials beyond conventional concrete:

• Improved efficiency
• Use with close meshed reinforcement
• For complex geometric shapes
• For slender components
• Generally where compaction is difficult
• Fast installation rates
• Noise reduction
• Reduced damage to health

How is this performance achieved?

• This concrete is extremely soft and flowable.
• SCC remains homogeneous and cohesive without segregation, separation or bleeding
• With the application of polycarboxylate based superplasticizers an outstanding fluidity at lowest water/cement ratios could be achieved.
• Special mix design considerations due to its high content of fines (? 0,125mm) and adapted grading curve
• Special high performance superplasticizers are necessary to produce SCC, in order to ensure a fluid concrete with controlled workability, a very high water reduction and a stable and cohesive concrete.

SCC Placing:

• Same procedure as with normal concrete, but faster and with less manpower
• SCC would not be freely discharged from a great height
• Conventional formwork can be used
• Pressure of fresh concrete on formwork is slightly higher than with conventional concrete
• If the concrete surface has to satisfy high aesthetic demands, the SCC should be placed under pressure, i.e. via a filling socket from below or by pipes which reach beneath the concrete surface level