Silica fume (microsilica) Concrete in Bridges

Abstract

It is noted that in the United States, SFC (silica fume concrete) has been used in more than 190 bridges, and is fast becoming an established material for bridge construction in Europe. This article describes the form of silica fume. The performance features of SFC and other silica fume modified materials are tabulated. SFC mix proportions, and its placing, finishing, and curing are described, as well as its performance. The low permeability and high electrical resistivity of SFC make its use desirable in bridges to better protect embedded reinforcing steel from corrosion. Other benefits include improved durability, high strength, high-early strength, abrasion resistance and improved bond. It is noted that best results occur when bonding grouts are used with overlay concrete, when water is prevented from prematurely evaporating from the concrete, and when the concrete is water cured.