Pot bearings are commonly used in post-tensioned superstructures due to their ability to support heavy loads, control articulation with guides, and offer a longer service life compared to conventional elastomeric bearings. However, longer post-tensioned structures often face issues with insufficient sliding surface length. Original designs have not always accommodated the time-dependent effects of creep and shrinkage, as well as the updated sliding requirements under seismic conditions. Additionally, pot bearings can deteriorate from sustained exposure to chlorides and continuous loads. The work associated with bearing replacement is costly, challenging, and time-consuming.
Particularly for pier columns, the design and construction of temporary support systems to facilitate pot bearing replacement present numerous challenges. Finite element analysis (FEA) is suited to assess load redistribution during jacking and temporary conditions while maintaining structural stability. Temporary supports require robust structural capacity to provide sufficient load transfer during jacking and supporting of the structure during the replacement work; however, the robustness of the temporary supports in proximity to the pier columns can limit access to the bearings and impact the constructability of the work.
This paper will explore these challenges and the unique aspects of replacing pot bearings on post-tensioned bridges. It aims to provide valuable insights and practical recommendations for engineers and practitioners involved in the maintenance and rehabilitation of post-tensioned bridges, ultimately contributing to the longevity and reliability of critical infrastructure assets.