NONDESTRUCTIVE EVALUATION OF TRUNNION BEARING PINS

Currently, there are several issues plaguing the bridge infrastructure in the United States. These structures are aging and reaching the end of their original design life while simultaneously experiencing increases in train speed, axle load, and train length. As a result of reaching the end of their original design lives, special attention must be given to evaluate the effects of deterioration such as corrosion and fatigue. This research project investigates the integrity of trunnion bearing pins using ultrasonic techniques that (1) minimize disassembling of the bearing, (2) minimize the lock time of the bridge, and (3) are nondestructive. The proposed technique uses an ultrasonic probe to inspect the bearing pin from the center hole as well as an ultrasonic transducer to inspect the pins from their faces. The results of this project show that the proposed method is capable of detecting discontinuities in the bearing pin such as the keyholes.