Title:
Monitoring and Assessment of a Prestressed Concrete Segmental Box Girder Bridge
Author(s):
Marc Savard and Jean-François Laflamme
Publication:
Symposium Paper
Volume:
342
Issue:
Appears on pages(s):
20-39
Keywords:
data analysis, finite element analysis, load tests, modal analysis, prestressed concrete bridge, structural damage, structural health monitoring
DOI:
10.14359/51725935
Date:
6/1/2020
Abstract:
Several of the first prestressed concrete segmental bridges in North America were built in Quebec, Canada.
The Rivière-aux-Mulets bridge was one of them. Built in the early 1960s, this bridge experienced several disorders
due to inadequate design criteria enforced at that time. Despite a structural strengthening in the late 1980s, a bridge
behavior follow-up has been required to ensure reliability. The structural health monitoring program implemented to
track structural disorders, along with results from modal analysis and diagnostic load tests, is presented with a focus
on the instrumentation and the data analysis. A three-dimensional finite element model was developed and calibrated
using the frequencies and mode shapes detected under ambient traffic conditions. Data analyses showed that the
expansion bearings were frozen, causing bending of the associated piers, which generated axial forces in the deck and
decompression of concrete in the area surrounding active cracks. This process enables premature failure of prestressing
tendons in the vicinity of these cracks, especially those located in the top flange, which is a corrosion-friendly
environment. Development of cracks and associated prestress loss caused a reduction in the bridge load-carrying
capacity. Analyses of health monitoring data led to acute assessment of the overall bridge structural performance.