• Thomas R. Hay, Ph.D., P.E

Bridge Pin Non-destructive Testing

TECHKNOWSERV CORP. (TKS) provides bridge pin non-destructive testing services to quantitatively assess cross-sectional area loss at hidden shoulders, barrels, and shear planes that are difficult or impossible to inspect visually. Our non-destructive testing engineering team has inspected bridge pins on over 100 bridges and other civil infrastructure assets over the last decade. This blog post summaries from of the insight gained for bridge pin nondestructive testing.


Bridge pin inspection is an important part of bridge fracture critical inspection programs. Bridge pins are steel cylinders produced by forging, casting, or cold-rolling processes. The most common bridge pin connection configurations include; bridge pin connected eyebars, bridge pin hangers, bridge bearing connections, hinge and bridge pin connections, bridge pin connected truss cord connections, and others.


The bridge pin connection can range in complexity from a simple system with two eyebar links or a multi-eyebar system with many links as shown in Figure 1. Due to the complexity of the bridge pin connection(s) is it absolutely essential to study the engineering drawing prior to bridge pin inspection and to identify the depth of shear planes, potential wear surfaces, shoulders and other changes in cross-sectional area. The pre-inspection effort is required to improve probability of detection of bridge pin defects while minimizing false positives bridge pin geometric features.