Unlike older "Allowable Stress" or "Load Factor" designs, LRFD is a probability-based approach. It is designed to ensure that the structural system of a bridge can withstand four primary limit states:
AASHTO LRFD Bridge Design Specifications, 5th Edition - 2010 Unlike older "Allowable Stress" or "Load Factor" designs,
Accounts for rare but severe events like earthquakes, vessel collisions, or ice loads. Major Revisions in the 5th Edition Unlike older "Allowable Stress" or "Load Factor" designs,
Prevents crack growth by limiting stress ranges caused by repetitive loading. Unlike older "Allowable Stress" or "Load Factor" designs,