This multi-faceted project included the evaluation of 10 post-tensioned (PT) concrete bridges and two complex nonredundant steel tension members (NSTM) for the Ohio Department of Transportation (ODOT) District 8. Project initiation included extensive review and research of design drawings, PT grouting logs and construction records and photos for the PT bridges. Equipped with the knowledge gained from this work, field evaluations were executed with focused efforts on key areas of concern, including tendon duct high points and anchorages.
Additionally, adapted rope access techniques were used on the NSTM bridges to minimize/eliminate the need for costly, time-consuming mechanical access and traffic control. The project work plan included risk-based protocols for non-destructive testing, tendon grout sampling/testing and borescope testing of key locations on the PT bridges.
A detailed report was developed for each bridge based on field findings, including the results of visual/tactile and PT invasive testing and inspection, supporting photographs and recommendations for long-term inspection procedures, maintenance and repair options. Significant voids with tendon corrosion and cracking were identified on select structures and rehabilitation plans were developed to address the found deficiencies. Construction cost estimates were also provided. Due to the specialized nature of the repairs, ODOT requested that technical support be provided during construction, including material specification review and site visits at key project milestones.
These efforts improve the long-term durability of these structures, giving ODOT District 8 additional peace of mind that these bridges will remain in-service for decades to come.