Guard Rail Fastener Evaluation for Major U.S. Transit Agency


CTLGroup was contracted to perform dynamic load testing on a guard rail fastener. This involved three axes of load, one vertical and two lateral. The vertical load was applied to the top of the running rail via 100 kip servo hydraulic actuator. The lateral loads were applied to the field side of the running rail and the gauge side of the guard rail with two 22 kip servo hydraulic actuators. A custom waveform was programmed to control the synchronization of the all three actuators. While the vertical actuator pushed down on to the running rail the lateral actuators pulled on their respective rails which simulates a train wheel pushing against the guard rail and the flange of the wheel pushing against the running rail.

The guard rail does not typically have load applied to it during qualification testing. The results of this testing showed that applying load to the guard rail does influence the results of qualification testing. These results were used to help develop a qualification testing specification, which includes applying load to the guard rail.