Effect of Voids in Grouted, Post-Tensioned Concrete Bridge Construction: Volume 2 – Inspection, Repair, Materials, and Risks

摘要: Post-tensioned (PT) bridges are major structures that carry significant traffic. These designed and constructed because they economical for spanning long distances. In Texas, there several signature PT bridges. the late 1990s early 2000s, state highway agencies identified challenges with structures: mainly corrosion of strands. The Texas Department Transportation (TxDOT) performed some comprehensive inspections their A consultant’s report recommended all ducts be re-grouted. However, environment in is very different than environments which strands were observed. objective this research was to evaluate activity correlate general environmental void conditions. To achieve objective, time-variant probabilistic models developed predict tension capacity subjected Using these models, structural reliability developed. probability failure a simplified structure HS20 HL93 loading conditions assessed. Both flexural serviceability Results indicate presence water chlorides can lead rates dependent on number exposed results presented Volume 1 report. assist TxDOT developing plan mitigate corrosion, studies assess repair grout materials, inspection methods, methods. addition, methodology optimizing repairs. topics 2 An Inspection Repair Manual also from separate should prevent infiltrating tendons — achieved part by repairing drain lines, ducts, protecting anchor heads as Recommendations inspections, repairs, materials provided, however, further potential formation galvanic coupling embedded both existing new grouts need