On-Site Acoustic-Emission Monitoring for a Prestressed Concrete BT-54 AASHTO Girder Bridge

Abstract

Acoustic emission (AE) data were investigated to better understand damage conditions in a three-span prestressed concrete girder bridge during a load test. The innovation lies in classification of crack extensions (stable or unstable) during the loading and holding processes. The gap in current literature addressed is a shortage of data and findings on bridges in operation and having inclined cracks. This manuscript addresses processing of AE signals recorded by piezoelectric sensors attached on two interior girders toward the obtuse corner of the bridge while under loading. Results showed indications of crack propagation beyond the existing cracks during both loading and load holds. Damage classification procedures based on AE data recorded during one loading and holding step are discussed. Shear strength analysis using modified compression field theory (MCFT) was performed to place the results in the context of potential overloads.