Computing the Reinforcement Yield Stress Ratio

AASHTO MBE 6A.5.4.2.2b provides an optional evaluation to limit the stress in reinforcement during permit rating cases. When permit rating factors are computing using WSDOT BDM Equation 13.1.1A-2 the live load arrangement (arrangement of legal and permit vehicles) that produces the governing permit moment rating factor is used for the yield stress ratio computation.

See Computing Emergency Vehicle and Permit Rating Factors for more information.