Abstract- The present study focuses on the “Experimental Study on the Development of Optimum Concrete Mix Proportion using Ultrafine Materials” for M30 grade concrete. The main objective of the research work was to investigate the effect of ultrafine materials such as Ultrafine Material (UF), UF100 and Microsilica on the compressive strength characteristics of concrete and to identify the optimum replacement percentage for achieving maximum strength and economy. Cement was partially replaced with ultrafine materials at different replacement levels of 2.5%, 5%, 7.5% and 10%. The experimental investigation included material testing, mix design as per IS 10262:2019, preparation of concrete specimens, casting, curing and compressive strength testing at 7 days and 28 days. Concrete cube specimens of size 150 mm × 150 mm × 150 mm were tested using Compression Testing Machine (CTM) as per IS 516 recommendations. The results obtained from the experimental investigation indicated that ultrafine materials significantly improved the compressive strength of M30 grade concrete. The improvement in strength was mainly due to better particle packing, reduction of internal voids and enhanced pozzolanic reaction. Among all ultrafine materials, Microsilica showed the best performance. Microsilica at 2.5% replacement achieved maximum average compressive strength of 55.32 MPa at 28 days, which represented 24.39% increase compared to conventional concrete. UF100 at 2.5% replacement also showed excellent performance with comparatively lower cost increase. The study concluded that lower replacement percentages such as 2.5% and 5% produced better results, whereas higher replacement percentages reduced compressive strength due to excessive ultrafine content.
Polampalli et al. (Fri,) studied this question.