SPI

Creative Concrete Innovations

Job Description: The Lewis Street Underpass was built in the 1930's with a low grade concrete. The railing concrete was spalling and falling on passing cars. The City of Pasco needed an economical way of preventing the spalling until the underpass could be replaced in the next 5-10 years. To create a more even rail surface, it was first hydroblasted at 10,000 psi, primed with 3 coats of Devoe 167 Penetrating Sealer and a quick-set grout was used to fill the larger gaps on the rail cap. Another coat of penetrating sealer sealed the grout before POLYSHIELD SS-100® was applied. The rail caps were then protected with 120 mils of POLYSHIELD SS-100® and the verti-cal rail surfaces with 60 mils. POLYSHIELD SS-100® was chosen for its strength, quick set-up time and cost-effectiveness. Because the under-pass has a high volume of pedestrian and vehicular traffic, a major concern for the project engineer was maintaining a quick turn-around time.

Follow-up Inspection: The city engineer checked the condition of the project 3 months after completion. He was pleased with POLYSHIELD SS-100® protection of the concrete and impressed by its resistance to vandalism.

Other Coatings Evaluated for Project: Paints and epoxy coatings including penetrating epoxy sealers were evaluated, but found ineffective for this project. The best option before looking at POLYSHIELD SS-100® was to apply a layer of sheet metal over the concrete rail surfaces.