Optimization of Silica Fume and Slag in Roller Compacted Concrete by Taguchi Method

Abstract

Roller Compacted Concrete Pavement (RCCP) is one type of concrete poured and compacted with the same machines utilized to construct heavy-duty pavements, log sorting, and parking. In this work, a combination of three factors was optimized to produce a sustainable RCCP. These factors were densified silica fume, ground granulated blast-furnace Slag, and mixing water contents. By weight, sulfate-resistant Portland cement was substituted with cementitious materials such as silica fume and slag in the amounts of (5, 7.5, and 10%) and (25, 27.5, and 30%), respectively. In addition, various percentages (5, 6, and 7%) of water content were utilized. Using the Taguchi approach, the impact of these factors was investigated based on the results of compressive strength and bulk density. The cubic specimens of compressive strength and bulk density, with 100 mm length, were tested at 7, 14, and 28 days. According to the results, the optimum percentages of silica fume, slag, and water contents were (5, 27.5, and 6%), respectively. Comparing the optimal mixture to the reference, the compressive strength enhancement was about 13.9%. According to Taguchi's study, water content has a most significant influence on the characteristics of RCCP than silica fume content. The slag content has the least impact on RCCP.