ABSTRACT
This paper presents an innovative approach for the evaluation of fatigue performance of highway bridges. The proposed method is a combination of analytical and experimental approaches. The steps include identification of critical components and ultrasonic stress measurements using a portable fatigue loading indicator which can be left unattended in the field under normal traffic. Miner’s rule is used to compute an effective constant amplitude stress which is applied to estimate the cumulative damage for a given period of time in-terms of equivalent 10 ksi constant amplitude stress cycles. A prototype instrument has been built and tested. This paper describes the methods used by a fatigue loading indicator and discusses some of the preliminary testing results.
