Question

Topic: Self-Compacting Concrete

1)Break the topic down to be able to write the abstract and find the list of references needed for the work

2) Preliminary abstract. The abstract should consist of one paragraph of about 250 words. The abstract should represent a concise statement of the scope, principal findings and conclusions of the paper.

2) List of references. The references should be more than 6 or more than 6 articles

Answer 1

Self - Compacting Concrete

Abstract

          Self-compacting concrete is developed in 1988, so as to acquire durable concrete structures. Since then, various experiments have been performed and the concrete has been used in practical structures in Japan. A rational mix-design method and self-compactability testing methods have been carried out to make the concrete the standard one. The method for achieving self-compactability involves not only high deformability of paste or mortar, but also resistance to segregation between coarse aggregate and mortar when the concrete flows through the confined zone of reinforcing bars. Okamura and Ozawa have employed the following methods to achieve self-compactability;

            (1) Limited aggregate content

            (2) Low water-powder ratio

            (3) Use of superplasticizer

The development of Self-Compacting Concrete (SCC), also referred to as ‘‘Self-Consolidating Concrete’’ and ‘‘High-Performance Concrete’’, has recently been one of the most important developments in the building industry. It is a kind of concrete that can flow through and fill gaps of reinforcement and corners of moulds without any need for vibration and compaction during the pouring process. It can be used in pre-cast applications or for concrete placed on site. SCC results in durable concrete structures, and saves labour and consolidation noise. In recent years, self-compacting concrete (SCC) has gained wide use for placement in congested reinforced concrete structures with difficult casting conditions. For such applications, the fresh concrete must possess high fluidity and good cohesiveness. The use of fine materials such as fly ash can ensure the required concrete properties. The initial results of an experimental program aimed at producing and evaluating SCC made with high-volumes of fly ash are presented and discussed. Nine SCC mixtures and one control concrete were investigated in this study. The content of the cementitious materials was maintained constant (400 kg/m3 ), while the water/ cementitious material ratios ranged from 0.35 to 0.45. The self-compacting mixtures had a cement replacement of 40, 50, and 60% by Class F fly ash. Tests were carried out on all mixtures to obtain the properties of fresh concrete in terms of viscosity and stability. The mechanical properties of hardened concretes such as compressive strength and drying shrinkage were also determined. The self-compacting concretes developed a 28-day compressive strengths ranging from 26 to 48 MPa. The results show that an economical self-compacting concrete could be successfully developed by incorporating high-volumes of Class F fly ash.

References

1. Masahiro Ouchi, “Self-Compacting Concrete.”
2. H. J. H. Brouwers and H. J. Radix, “Self-Compacting Concrete: Theoretical and experimental study.” Cement and Concrete Research, Vol. 35 (2005), pp. 2116 – 2136.
3. Bouzoubaâa and M. Lachemib, “Self Compacting Concrete Incorporating High-Volumes of Class F Fly Ash: Preliminary Results.” Cement and Concrete Research, Vol. 31, No. 3, Mar. 2001, pp. 413-420.
4. H. Okamura, “Self-compacting High-Performance Concrete” Concrete International, Vol. 19 (7) (1997), pp. 50 – 54.