Effect of Silica Fume and Steel Fibers on the Hardened Concrete Properties

Abstract

This research is aim to produce High Performance Concrete (HPC) in Sudan by using materials which are available at the local markets. Different trial mixes are used to obtain a compressive strength exceeding 80 MPa. The research includes the replace percent of cement by (silica fume) and Steel fiber, with cement and aggregates (crushed stone and quartz sand). The effect of adding different percentage (10%,20%,30%) of silica fume on main properties of HPC, i.e., compressive strength, density of concrete and flexural strength was 30%. The test results revealed that it is possible to produce HPC in Sudan, with compressive strength in excess of 88 MPa using materials which are available at the Sudan, if these are carefully selected and properly mixed in such a way to optimize grain size distribution. Based on the results of this research, the optimum percentage of silica fume necessary for producing HPC is about 20 % of cement weight and the optimum percentage of silica fume necessary for increase concrete density and increase flexural strength is 30% of cement weight.