Abstract: Methods, systems, and apparatus are disclosed for determining rail safety limits. A first example method is disclosed for determining rail safety limits, including identifying a target rail neutral temperature for a portion of continuous welded rail. The method also includes monitoring a longitudinal stress for the portion of continuous welded rail and monitoring an ambient rail temperature for the portion of continuous welded rail. The method further includes determining a present rail neutral temperature based on the longitudinal stress and the ambient rail temperature. According to the example method, the present rail neutral temperature is compared to the target rail neutral temperature to determine whether a failure of the portion of continuous welded rail has occurred, and an alert is reported if the difference between the present rail neutral temperature and the target rail neutral temperature is within a predetermined range.

Abstract: A rail stress monitoring system is disclosed. This system includes a sensor module that further includes a sensing device that is adapted to be mountable directly on a length of rail. The sensing device further includes a generally flat metal shim and at least one, and typically two or more, sensors mounted on one side of the shim. The sensors are typically strain gauges, which are mounted on the shim in a specific, predetermined configuration. At least one data acquisition module is in electrical communication with the sensing device and a data processing module receives and processes information gathered by data acquisition module.