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1Â Â The use of post-tensioned concrete facilitates the construction of economical and durable structural members in bridge construction, lengthening spans and improving service behavior. Post-tensioning, a construction technique in which a precompression is applied to a concrete member, is found in many structural bridge members, such as girders, decks, pier caps, and piers. Specific aspects of this type of construction demand careful consideration throughout the structureâs service life because they directly affect structural performance and durability. Recently in the United States, repair and maintenance issues related to post-tensioned bridges have gained attention in light of instances of serious tendon degradation in structures built prior to 2000. Since the early 2000s, the industry has made significant advancements to improve the quality of post-tensioned structures, taking action to improve grout materials (including the introduction of thixotropic prebagged grouts), quality control, filler injection procedures, edu- cation of personnel, and basic details. Bridge owners have refined requirements for certification, inspection criteria, standard details, approved products, and performance. Still, agencies are addressing issues in both older and newer post-tensioned structures, and the need for continued improvement remains. Although issues are generally approached by bridge owners on a case-by-case basis, knowl- edge transfer will improve post-tensioned structure integrity while reducing maintenance and repair efforts. This synthesis includes results from a survey distributed to state departments of transportation that gathered information on the practices used by bridge owners to repair and maintain post-tensioned bridges. The goal of this document is to further facilitate knowledge transfer across agencies, aiding bridge owners in the identification and implementation of successful construction, repair, and maintenance practices. Introduction
