Impregnation Technique Provides Corrosion Protection to Grouted Post-Tensioning Tendons

Thousands of bridge structures rely on grouted post-tensioning (PT) tendons. Problems with grouting techniques and grout materials have resulted in bridges with grout voids, chloride contaminated grout and soft grout. These problems have promoted corrosion and failure of post-tension tendons, some within 6 to 17 years of service. The Florida Department of Transportation (FDOT) has spent more than $55 million (USD) repairing 11 post-tensioned bridges to date. A cost-effective corrosion mitigation technique has been developed to minimize the corrosion of PT tendons and extend the service life of bridges which have grouting issues. This paper describes the development and implementation of this technique on grouted PT bridges.