Integral-Abutment Bridges: Geotechnical Problems and Solutions Using Geosynthetics and Ground Improvement

The integral abutment bridge (IAB) concept was developed at least as far back as the 1930s to solve long-term structural problems that can occur with conventional bridge designs. Unfortunately, the IAB concept as executed historically turns out to have its own inherent post-construction flaws. However, they are fundamentally of a geotechnical, not structural, nature. As a result, bridge engineers, who are more familiar with dealing with structural issues, have been slow to recognize the true source of IAB problems and develop appropriate permanent solutions for them. Thus IABs represent an interesting case study in soil-structure interaction that requires the coordinated attention of both structural/bridge and geotechnical engineers working as a multidisciplinary team if the concept is to be improved for better long-term performance. This paper is intended to be a contribution toward that goal and illustrates the potential use of modern geotechnolgies for IAB problem solving.