KHIT 134, Proposal for Steel Bridge Coating Inventory - Phase I

Lead-based coatings on KYTC steel bridges are being removed and replaced over the past 25 to 30 years but a number of bridges still have lead coatings. The typical replacement coating has been zinc-based systems. Older projects, those in 1980s/1990s, used inorganic zinc primers with vinyl top coats for replacement. Those coating systems are reaching the end of their service life and are in need of either repair or replacement. Bridge maintenance painting projects since 2000 usually used organic zinc primers as part of a two or three coat system. Some of these have localized coating failures in high stress areas. KYTC currently maintains in excess of 1100 steel bridges. At current expected coating service life, properly maintaining the protective coatings of these bridges will require painting at least 50 bridges per year. An up to date inventory of KYTC steel bridges with coating condition assessment is the first step for KYTC bridge maintenance personnel to develop a plan for maintaining bridge protective coatings. Based on these assessments, maintenance coating schedules as well as economical bridge coating strategies such as spot/zone painting or over-coating would be developed. A coatings maintenance plan will include a projected budget which will support requests for bridge maintenance funding. Part of an independent inventory assessment will be to correlate KYTC bridge inspectors’ coatings assessment during biennial inspections in BrM. As part of Phase I KTC will undertake the following tasks: 1. Mine BrM data for all steel bridges including toll and county bridges to sort them by their current element coating condition. 2. Then sort steel bridges by their bridge type (ex: truss, plate) and district. 3. Contact all district bridge engineers with the prepared list from tasks 1 and 2 to prioritize bridges based on engineer’s assessment. 4. Present the final list compiled from all the above tasks to Division of Maintenance TEBM for future field assessment.