Condition assessment of prestressed concrete channel bridge girders using acoustic emission and data-driven methods

Abstract

In the United States, a significant proportion of bridges are contending with aging and decay, necessitating reliable inspection methods for ensuring safety and functionality. Traditional visual inspections, while common, are often subjective and labor-intensive. This study proposes an innovative approach using Structural Health Monitoring (SHM) systems, particularly focusing on Acoustic Emission (AE) techniques. AE is chosen for its sensitivity to the early stages of material damage. The research involves flexural tests on six prestressed concrete channel bridge girders from 30-ft span bridges, originally constructed in the 1960s, at the University of South Carolina. These girders were monitored using AE during tests and were previously rated for condition based on the Specifications for the National Bridge Inventory (SNBI). The contribution of this paper is the development of intensity analysis charts from AE data, offering a more objective and comprehensive assessment of girder conditions. These charts, calibrated against theoretical cracking load and cumulative signal strength analysis, are capable of evaluating deterioration irrespective of initial conditions, thereby aiding in determining the condition factor for bridge load rating.