The seating length is defined as the distance between the end of the girder and the end of the abutment where it is placed. What is this distance commonly called?

• A. Seating length
• B. Bearing length
• C. Span length
• D. Overhang length

Answer: (A)

In bridge seating terminology, the distance from the end of the girder to the end of the abutment where the girder sits is described as the seating length. This term highlights the portion of the girder that is actually resting on the abutment seat and thus carries load through the bearing. It’s the specific span of the beam that engages with the abutment seat, distinguishing it from other lengths that describe different relationships. The span length refers to the overall distance between supports, the overhang length describes any portion of the girder that extends beyond a support, and bearing length concerns the contact area of the bearing itself. Therefore, the defined distance is best called the seating length because it directly names the portion that sits on the abutment and forms the seating interface for load transfer.