Load rating is the determination of the safe live load carrying capacity of a highway structure. It is usually expressed as a Rating Factor (RF) or in terms of tonnage for a particular vehicle. Rating frequency may vary by owner but is usually performed in the design stage, initial inventory inspection, when there is a change of live loading or dead load on the structure, or if there is a physical change in any structural member of the bridge. The Manual for Bridge Evaluation, Third Edition, 2018 (MBE) implies that decks should be rated as a main load carrying component of the superstructure. Some owners may overlook this requirement for conventional reinforced concrete decks but require rating of grid reinforced concrete and Exodermic^® decks for new construction.

Click here to view this latest technical bulletin (and all previous) and read how the BGFMA V3.1 design program can be used to supplement the MBE and AASHTO LRFD Design Specifications to load rate a deck (including an example).