Development of Self Compacting Concrete using Silica Fume

Development of SCC is a desirable achievement in the construction industry in order to overcome the problems associated with cast-in-place concrete. SCC is not affected by the skills of workers, shape, size and amount of reinforcing bars used or arrangement of different structural elements, but due to its high fluidity and resistance to segregation, it can be pumped to longer distances. The main reasons for the employment of self-compacting concrete is to shorten the construction period, and to assure compactions in the structure, especially in confined zones where vibration is difficult, and to eliminate noise due to vibration. A simple mix design for SCC proposed by Nan su et al. is used for achieving the trial mixes. The trial mix which satisfies the rheological properties as per EFNARC guidelines and the corresponding developed mix which gives maximum compressive and splitting tensile strengths are used in the present work. Cement is replaced with varying percentages of silica fume (SF) ranging from (0-15%) at an interval of 2.5%. SCC with 5% silica fume shows better results when compared to other replacement levels. Hence it is found that silica fume can be effectively used as an alternate for cement replacement.