Mobile, Non-Contact System for RNT and Rail Stress Measurements

Continuous Welded Rail track, despite the significant advantages, is prone to buckling and rail breaks due to the inability to expand and contract freely to temperature changes, compromising, thus, the integrity and safety of the track. To date, there is no robust way to measure or monitor the rail longitudinal stress or the stress-free temperature (RNT) without disturbing the railroad track. Our proposed innovation is a mobile, non-contact, reference-free system that is free of the shortcomings of existing and competing techniques. The technology uses 3D imaging technology for rail shape measurements along with a patented technology that correlates the shape changes and deformations of the rail during temperature changes to the RNT and the longitudinal rail stress. A system like ours is the only technology that determines the RNT and stress of the rail in a single acquisition without disturbing the track structure or disrupting operations. It does not require a known zero-reference, and it operates regardless of the state of stress (tension/compression) in the rail. It is the only technology that has the potential to acquire measurements of both rails simultaneously in less than 10 minutes per location by a two-member trained crew without disturbing the track.