What is the purpose of a bridge load rating?

• A. To determine the safe load-carrying capacity and guide postings and permit decisions.
• B. To measure traffic speed
• C. To estimate construction cost
• D. To determine color coding of deck painting

Answer: (A)

A bridge load rating reflects the safe live-load capacity of a structure under its current condition. It combines the bridge’s geometry, materials, current deterioration, and redundancy to determine how much weight the bridge can safely carry without overstressing any part of it. The rating directly informs posting and permit decisions: if the rating supports normal traffic, no special limits are needed; if it’s reduced, posted weight limits or special permits for heavier vehicles are required to protect safety and extend the bridge’s life. This is not about how fast traffic moves, construction costs, or deck painting colors.