Diagnostics of Concrete Box Beam Bridges using Wireless Sensors and Finite Element Analysis

Abstract Three pretensioned adjacent concrete box beam bridges were studied with a structural health monitoring (SHM) paradigm based on strain measurements and finite element static analysis. An accurate model for one bridge and an approximate model for the other two were created using ANSYS software. The analysis was used to calculate the strains generated by six concentrated loads that mimic the presence of a truck. Pristine and damage scenarios were implemented, and the associated numerical strains were compared to the experimental strains measured with proprietary wireless sensors during a truck test. As the results from the approximate models revealed that the approximations did not capture the field response of the bridge, the accurate model applied to one bridge was extended to the other two. The comparison between numerical and experimental results revealed the presence of non-critical anomalies related to strain distribution across adjacent beams. Such issues were confirmed with the examination of the historical strains streamed for several months to a repository, using simple data processing strategies. The intellectual contribution of the work resides in the combination of finite element analysis and SHM paradigm on three existing bridges with very similar structural characteristics. This combination showed the limitations of approximated modeling and the possibilities to unfold critical and non-critical issues with SHM.