Concrete is a very important construction material that contributed immensely to the development of the civilization. The material has seen tremendous development from High performance concrete, High Early Strength Concrete, High Strength Concrete, Self Compacting concrete.
With increase in demand in the rate of construction and demand to decrease different type of pollution, including sound pollution, Self Compacting Concrete or SCC was developed. This type of concrete has more mortar in it by increase in the amount of fly ash, Sand/Aggregate ratio, etc. As a result concrete behaves as a solution with Coarse Aggregate floating in it. This type of concrete has great potential in future as this type of concrete does not require vibration.
Present-day self-compacting concrete can be classified as an advanced construction material. As the name suggests, it does not require to be vibrated to achieve full compaction. This offers many benefits and advantages over conventional concrete. These include an improved quality of concrete and reduction of on-site repairs, faster construction times, lower overall costs, facilitation of introduction of automation into concrete construction. An important improvement of health and safety is also achieved through elimination of handling of vibrators and a substantial reduction of environmental noise loading on and around a site.
Valeria et al. mentions that high fineness of marble powder is proved to be very effective in assuring very good cohesiveness of mortar and concrete, even in the presence of super plasticizing admixture, provided that water to cement ratio was adequately low. Marble powder has a very high Blaine fineness value of about 1.5 m2/g, with 90% of particles passing 50?m-sieves and 50% under 7?m.
Similar work has been reported by the research work led by Dr. Supratic Gupta. They have found that with an increase in the mortar density, the segregation index increases irrespective of other parameters. Also increase in volume of fines (cement and fly ash) at the cost of decrease in sand, the segregation index decreases.
Hence, sand plays a more crucial role than the fines towards improving segregation resistance. Since Marble powder has higher density, it is assumed that this would improve the segregation resistance of the Self Compacting Concrete.
Hanifi Binici et al. found that Marble dust concretes had higher compressive strength than that of the corresponding Lime stone dust and control concrete with equivalent w/c and mix proportion, the results indicate that the Marble dust concrete would probably have lower water permeability than the lime stone and control concrete. It is in this respect that marble powder is expected to play an important role in Concrete, and SCC in particular.
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