Field Impregnation Techniques for Highway Concrete

The corrosion of reinforcing steel due to the penetration of deicing salts poses a considerable problem in bridge decks. One approach which has received much attention has ben impregnation with a liquid monomer followed by polymerization to effectively seal the capillary pores against salt intrusion. The feasibility of impregnating a bridge deck to a depth of 4 in. or more under field conditions is demonstrated herein. Since the present deep impregnation techniques are costly in terms of energy, materials, and time, simplifications and improvement would be desirable. Herein, results of preliminary experiments with the use of a pressure-mat technique for mechanically assisting monomer or sealant penetration are described. It is shown that pressure mechanically applied to patterned rubber mats can effect uniform impregnation with a monomer such as methyl methacrylate or a sealant such as tar or linseed oil in reasonable times. Such an impregnation could conceivably be effected using rollers.