BRIDGE LOAD RATING USING AN INTEGRATED LOAD TESTING AND FINITE ELEMENT ANALYSIS APPROACH: A CASE STUDY

Bridge load rating is the primary decision tool that is currently in use to evaluate and predict bridge performance under various loading conditions. Traditional bridge rating calculations involve calculating the load carrying capacity of the structural elements based on design plans, field inspection reports, and engineering judgment. Experience shows that bridge performance is always under-estimated using this simplified approach and in many cases results in placing unnecessary load restrictions on bridges. Bridge diagnostic load testing has been widely recognized as a more reliable and accurate method for bridge rating. However, the time and cost involved in conducting bridge load testing has been a major impediment to employing this valuable tool on a large scale. Bridge owners can typically only afford to perform load testing for major bridges and under critical circumstances. The need for more cost- effective and easy-to-implement methods to perform bridge load testing and rating analysis is well evident. In this paper, the use of an integrated system to conduct bridge load testing, finite element analysis, and rating is demonstrated. The system consists of load testing instrumentation and data acquisition hardware as well as four software components to perform structural analysis and rating calculations. A case study of a prestressed concrete bridge is presented to demonstrate the seamless integration of the load testing and analysis processes.