Time-Dependent Behavior of a Concrete Integral Abutment Bridge

Abstract

Time-dependent behavior of an integral abutment bridge near Rochester, Minnesota, was investigated from the beginning of construction through 7 years of service by using field data collected from more than 150 instruments installed in the bridge during construction. Long-term bridge shortening was observed from the readings of horizontal extensometers installed behind the abutments. Measured pile curvatures steadily increased with time. To understand this unexpected bridge behavior better, a time-dependent numerical study using the creep and shrinkage models from American Concrete Institute Committee 209 was conducted. The results obtained in this research indicate that concrete creep and shrinkage had a significant effect on the behavior of the concrete integral abutment bridge over the course of the 7-year study.