ABSTRACT

The AASHTO LRFD Bridge Design Specifications (AASHTO 2016) defines Strength IJ limit state for various agencies to consider the load combination relating to the use of bridges in the United States by owner-specified special design permit vehicles, evaluation permit vehicles, or both. However, the code calibration process, initially performed in 1994, was applied only to the Strength I Limit State (Nowak 1999). Additionally, the configuration and characteristics of permit vehicles vary from state to state. This study presents the comparison of load effects among design permit vehicles from different agencies. Then the design permit vehicle of New Jersey Department of Transportation (NJDOT) is assessed using five years of permit vehicle records. In comparison with the current AASHTO live load factor of 1.35, the averages of the bias ratios at the 75-year level are found to be 1.31, 1.23, and 1.16 for the positive moment, shear, and negative moment, respectively.