Starting in 2007, the American Association of State Highway and Transportation Officials (AASHTO) adopted the Load and Resistance Factored Design (LRFD) Bridge Design Specifications as the mandatory standard by which all future bridge structures should be designed. New Jersey committed itself to adopting the LRFD Specifications in January 2000. The LRFD Specifications consider the variability in the behavior of structural elements through extensive statistical analyses and, therefore, continue to be improved. However, many of the Specifications’ design approaches and methodologies have been adopted with limited or virtually no experimental validation. Hence, there became a need to validate these new design procedures and models as well as the behavior of LRFD designed bridge structures.

The main objective of this study was to validate the AASHTO LRFD Specifications through fieldtesting of the Doremus Avenue Bridge — New Jersey’s first AASHTO LRFD (1998) design. In addition, long-term monitoring of the bridge fatigue life was also implemented. In particular, the study evaluates the AASHTO criteria for composite design with respect to the requirements for shear connectors, the effects of designing for deflection control as well as using higher concrete strengths on deck stiffness and stresses. Results included new simplified equations for calculating Girder Distribution Factors (GDF) and effective flange width criteria in addition to establishing major live load spectra for various WIM NJ sites. Deflection measurements and simulation using Extreme Value Theory (EVT) shows that the 75-year maximum deflection is within the NJDOT deflection limit of L/1000. However, future research is needed to establish if the L/1000 limit is indirectly helping to control vibration of the superstructure. Moreover, a new procedure for predicting the remaining fatigue life is established using WIM truck data, rain flow, and structural analyses.