Post-service Evaluation of Pin-connected Truss Joints

Pin joints of recently replaced pin-connected trusses of a Class I railroad are examined by the Transportation Technology Center, Incorporated (TTCI) in this article. These pin-connected trusses represent a small percentage of the steel bridge inventory by length on the North American Class 1 railroad system and an even a smaller percentage of the total bridge inventory. However, many of these pin-connected trusses are in service at critical locations on busy mainlines and important secondary lines. These pin-connected trusses represent a distinct period in railroad construction and World War I represents the end of the construction period. Therefore, the replacement of many of these trusses will be expensive and could create operational issues. Pin-connected trusses are a major concern because of conditions associated with their age and design load.