Fatigue for steel member and connection details in most bridges can be effectively analyzed through strain gage monitoring of the live load stresses or displacements due to operating service loads. Since the live loads and the corresponding stresses induced are typically random in nature, various stress cycle counting algorithms must be applied to strain measurements acquired from a sufficiently long enough duration to capture the representative loading spectrum for the structure. The stress cycle counts are then evaluated to determine the effective stress ranges and to assess the fatigue life. In cases where the structure, its detailing and/or the loading environment are particularly complex, a spectrum of additional tools may need to be employed to obtain a more complete and reliable fatigue assessment. These additional tools can include finite element analysis, material sampling and laboratory testing, local NDE of the detail, controlled truck load testing and vibration measurements.
Intelligent Infrastructure Systems has experience with the complete spectrum of analytical and experimental tools and techniques that may be required to evaluate a fatigue problem. We can design and implement a fatigue analysis program that is most appropriate for the structure/details that need to be evaluated and in accordance with the relevant AASHTO, AWS, and ASTM Standards.
For more information about our Fatigue Analysis services, please contact us at firstname.lastname@example.org