Advanced Neutral Temperature Estimation using Solitary Waves (ANTEUSW)

TRB's Transit Innovations Deserving Exploratory Analysis (IDEA) Program Final Report 86: Advanced Neutral Temperature Estimation using Solitary Waves (ANTEUSW) explores a new nondestructive evaluation method able to determine the axial stress and the neutral temperature of continuous welded rails.

Continuous welded rails (CWRs) are widely used in rail transportation. Typically, they are laid under tension in order to counteract the thermal expansion that occurs in warm days. Ideally the state of stress is such that the rail neutral temperature (RNT), i.e. the temperature at which the net stress in the rail is zero, is comprised between 90°F and 110°F. Over the years, operational conditions and maintenance result in the decrease of the RNT to an unknown value, increasing the risk of buckling, a structural problem that causes several derailments every year. As the accurate knowledge of the RNT or of the current stress helps rail operators to estimate the temperature at which a rail will likely buckle, there is a need for a reliable nondestructive evaluation (NDE) methods able to estimate the neutral temperature or the longitudinal stress of CWRs anytime and anywhere along the rail network.