07-08-2012, 03:08 PM
Self Consolidating Concrete
Self Consolidating Concrete.pptx (Size: 1.2 MB / Downloads: 59)
What is SCC?
A high-performance concrete that flows under its own weight to fill completely the formwork without vibration or mechanical consolidation.
developed in 1980s in Japan
Strength and durability is same as conventional concrete.
How is SCC made?
High-range water reducer admixture (polycarboxylate)(superplasticizer)
High paste content
Viscosity Modifying Admixture(VMA)
Increased amount of Fine material
-fly ash , lime stone filler
SCC Mix Proportioning
W/c Ratio Kept 0.45%
The aggregates used in all mixes were of saturated surface dry condition.
Cement/aggregate ratio (C/A) ratio was 0.25
The fine/coarse aggregate ratio (S/G) was 1.
Maximum coarse aggregate size was 20mm.
Recommendations for Mix
Design to prevent static segregation.
Set limits on flow length to prevent dynamic segregation.
Set limits on paste contents to avoid shrinkage.
Avoid low W/C ratios to reduce shrinkage.
Fresh SCC properties
Flowability: flows easily at suitable speed into formwork
• Passing ability: passes through reinforcements without blocking
• Segregation resistance: the distribution of aggregate particles remains homogeneous in both vertical and horizontal directions
– Static segregation due to gravity, vertical direction
– Dynamic segregation due to flow, horizontal direction