A Study on Influence of Coarse Aggregate Size on Fresh Properties of Self-Compacting Concrete (SCC)

Accurate descriptions of the shape and surface texture, or roughness, of aggregate
particles need to be determined before the effects of these parameters on the
properties of Self-Compacting Concrete (SCC) can be evaluated. In 1980s, SCC is
developed in Japan, Sweden and France. SCC has recently been one of the most
important developments in building technology, usually used in pre-cast applications
or for concrete placed on site. SCC is characterized by extreme fluidity, a moderate
viscosity, no bleed water and no blocking may occur during flow. SCC assures
compaction in the structure; expecially in confined zones where vibrating
compaction is difficult. SCC results in durable concrete structures, reducing costs
and improving workmanship as well as working conditions. l\1ost importantly, SCC
can reduce or even completely eliminate the need to vibrate which consolidation
noise. The previous research has proven that the workability of SCC is better than
normal concrete and Researchers also conclude that tbe aggregate content and size
that possible to be added in the concrete mixture, in order to enhance the concrete
performance but the studies had not been done to examine the coarse aggregate size
that maximizes workability and strength. The project is carried out based on this
finding that there is not a systematic study on the sec that is being produce
according to specific range of sizes. This research describes tbe investigation of the
effect of coarse aggregate size towards the fresh properties of SCC and provides a
reference on coarse aggregate size that maximizes SCC workability and compressive
strength. The analysis focused on the question of how far the coarse aggregate in
sec differs from other aggregate size in term of workability and compressive
strength. The Kajima Box test, V-funnel test and slump flow test are used to
determine the fresh properties while for the hardened concrete properties, 7 and 28
days compressive strength test are carried out to verity that its strength is achieved.
These results provide information on the filling ability, slump flow, flow time,
compressive strength at specific size of ranges 3.36 mm- 5 mm, 5 mm- 10 mm, 10
mm- 14 mm and 14 mm- 20 mm. At the end of the project, comparison of fresh
properties and compressive strength between coarse aggregate sizes under study
revealed the best range size range 3.36 mm - 5 mm. The size of coarse aggregate
plays a significant role in determining the fresh properties of SCC. The project may
assist in designing optimal sec performance for construction industry.