Title: Ensuring High Quality Silica Fume Concrete Overlays

Author(s): C. Ozyildirim

Publication: Symposium Paper

Volume: 153

Issue:

Appears on pages(s): 675-686

Keywords: chlorides; curing; permeability; placing; resurfacing; silica fume; Materials Research

DOI: 10.14359/1092

Date: 6/1/1995

Abstract:
Thin concrete overlays are widely used for protection against corrosion during the rehabilitation of concrete bridge decks. These overlays protect the reinforcing steel from the ingress of chlorides from deicing salts or the marine environment. The Virginia Department of Transportation (VDOT) has successfully used thin concrete overlays containing silica fume (minimum thickness 1-1/4 in. [32 mm]) to provide a high resistance to the penetration of chlorides into the concrete. Silica fume concrete (SFC) overlays are now an acceptable alternative to other rehabilitation procedures. In the development of SFC overlays, certain problems were encountered at different phases of production and construction, including proportioning, mixing, bonding, consolidation, and curing. These problems and their solutions are discussed in this paper, and recommendations are made for minimizing problems in future installations.