Information Self Compacting Concrete SCC

Information Self Compacting Concrete SCC

INTRODUCTION
A special type of concrete of flowing consistency, developed initially in Japan in 1980's to offset the growing shortage of skilled labour.
The composition in addition to cement and water, consists of high amount of super plasticizer, high powder content..


REQUIREMENTS OF CONSTITUENT MATERIALS

CEMENT
Type depends on the overall requirements for concrete such as strength, durability, etc.
C3A content higher than 10% may cause poor workability retention.


Typical cement content
350 to 450 kg/cum.
Cement > 500kg/cum cause increase in shrinkage.
Cement < 350kg/cum demands other fine fillers such as flyash ,pozzolan, etc.


AGGREGATES
SANDS

Fines less than 0.125mm - powder, very important for SCC.


COARSE AGGREGATE
All types of aggregates are suitable for SCC, Normal maximum size is generally 20mm, Crushed aggregates improve strength while rounded aggregate improve flow.


MIX PROPORTIONING FOR ACHIEVING SELF COMPACTION
Changes in the coarse aggregate content.
Changes in the fine aggregate content.
Use of super plasticizers.
Combination of most suitable water cement ratio and superplasticizer powder ratio.


PROPERTIES OF HARDENED SCC
Water-binder ratio0.25 to 0.40
Air content(%) 4.5-6.0
Compressive strength (age: 28 days) (MPa) 40 to 80 depend upon the design mix.
Compressive strength (age: 91 days) (MPa) 55 to 1005. Splitting tensile strength(age: 28 days) (MPa) 2.4 to 4.8


ADVANTAGES OF SCC
Faster construction
Reduction in site manpower
Better surface finishes
Easier placing
Improved durability
Greater freedom in design
Thinner concrete sections
Reduced noise levels, absence of vibration
Safer working environment.


CONCLUSION.
Self-Compacting Concrete is considered to be the most promising building material for the revolutionary changes on the job site.
We can create durable and reliable concrete structures using SCC