Lateral capacity and repair of corrosion-damaged pile bents, part 3: Carbon-fiber-reinforced polymer application and strength testing

Pile-bent-type bridge piers support a large fraction of today’s overwater bridges. In aggressive environments, the thin concrete cover typical of prestressed piles makes the piles vulnerable to corrosion damage not encountered by submerged piles supporting water-level footings. This vulnerability is due to the repetitive cycles of wetting and drying in the regions above and within the tidal sea level through which the piles extend. This paper is the final paper in a three-part series that explores the effects of corrosion damage on pile bents and demonstrates the effectiveness of carbon-fi¬ber-reinforced polymer (CFRP) repair of severely corroded piles. This paper reports a study of the lateral load capacity of a one-third-scale bridge pile bent constructed with five piles that had greater than 96% cross-sectional steel strand loss and were repaired with CFRP material to restore bending resistance. The lateral load capacity of the repaired pile bent met and exceeded that of an undamaged, uncorroded pile bent built from the same lot of prestressed concrete piles, which had been tested 20 years earlier. Test results also demonstrated the suitability of numerical modeling to predict the strength gain from CFRP wrap repairs. The findings are encouraging and support the applicability of new technologies to maintain aging infrastructure.