Non-destructive testing (NDT) of a segmental concrete bridge scheduled for demolition, with a focus on condition assessment and corrosion detection of internal tendons.

PDFTech ReportBDV29-977-05Nondestructive testsAcoustic emission testsInductanceConcrete bridgesUnited StatesFloridaFlorida International UniversityAzizinamini, AtorodFlorida International University. Dept. of Civil and Environmental EngineeringFlorida. Dept. of TransportationRehmat, Sheharyar eSadeghnejad, AmirFancy, Saiada FuadiChunn, BrianValikhani, AlirezaMohammadi, AlirezaTaghinezhadbilondy, RaminMoravej, MohammadtaghiGull, Jawad H.Yakel, AaronLau, KingsleyUS Transportation CollectionThe service life and durability of prestressed concrete in bridges are vulnerable to corrosion damages due to many factors such as construction, material, and environment. To ensure public safety, it is important to inspect these structures and to develop appropriate mitigation measures for corrosion damages. The availability of Non Destructive Testing (NDT) technology has made it possible to evaluate the condition of a bridge without invasive removal of concrete. A project bridge located in Fort Lauderdale, scheduled for demolition, provided an opportunity to carry out various on-site and post-deconstruction tests. An analytical study was carried out for demolition sequence, and segments of the bridge were transported to Florida International University (FIU). These segments were used as a test bed setup, and additional laboratory tests were conducted to evaluate some of the NDT technologies which can be extended to the testing of actual structures. The on-site field tests using impulse response showed a reduction in global stiffness, due to partial deconstruction while acoustic emission demonstrated possible use in detection of vibration due to tendon breakages. During the field tests, infrared thermography assisted in identification of ducts with deficient grout and the use of infrared thermography was further investigated in laboratory tests. The method has shown the possibility to detect wire breakages in encapsulated grout. A methodology to detect tendon damages in internal tendons in the presence of secondary reinforcement was investigated using the magnetic flux leakage method for laboratory test setup and validated on decommissioned test segments. The inductance method showed promising results for laboratory and segment tests, but obscuring of signals due to mild reinforcement is a challenge