FRT 196, Remove and Evaluate a Weld Crack on U29' on the I-65 JFK Bridge over the Ohio River at Louisville

A linear weld flaw has been detected in flange-to-web fillet weld of the downstream upper chord of the truss on the I-65 John F. Kennedy Bridge at Louisville. The location where the flaw is located was the site a previous repair in the mid-1990s. The Kentucky Transportation Cabinet has requested that the weld flaw be extracted from the chord member (an H-beam) and that the flaw be evaluated to determine if it is an active growing crack (related to fatigue). KTC is proposing to place a “dog-bone” cut in the beam web and then core out the web/weld segment containing the weld flaw. The coring will extend into the web until it intersects with the shank of the “dog-bone”. The cut area will be evaluated using magnetic particle testing. The core segment will x-rayed to determine the position of the flaw. Saw cuts will be made to remove most core material bordering the flaw. The core will then be immersed in liquid nitrogen and subsequent split to expose the surfaces of the flaw/crack. The exposed flaw will be subjected to visual and enhanced inspection using a scanning electron microscope. A failure expert will examine the fracture surface and provide a brief report on the nature of the flaw.