Case Study / Bridge Foundation

Elevation® Geofoam Helps Stop Bridge Foundation from Moving and Get Traffic Moving

Traffic on I-94 ⎯ the main conduit between Chicago and Detroit ⎯ was at a dead stop.

The busy stretch of highway between the two cities had to be closed at the overpass of Riverside Drive during road reconstruction because of a foundation settlement problem. The road crew left work one day and when they returned the next morning, the bridge had shifted more than 12 inches.

There are a large number of springs along Riverside Drive, and according to Bobbi Welke of the Southwest Michigan Department of Transportation (MDOT) office, wet soil “strongly contributed to different elements of the bridge” moving several inches. This issue was known at the beginning of the reconstruction project, but hadn’t been addressed correctly.

Geofoam, which had always been part of the original design because of the settlement issues at this bridge abutment, was scheduled to be placed on both sides of the freeway to remediate the settlement. Before the geofoam was placed, however, the bridge shift occurred. After the 12-inch movement took place, MDOT engineers went back and reevaluated the soil conditions. They realized the issues were more extensive than originally thought and that additional geofoam was needed for stabilization. With this new knowledge, MDOT engineers devised temporary shoring to keep the bridge from shifting further while work resumed. This allowed traffic to begin flowing again and workers to get back to working on a permanent solution.

The engineer’s new design called for 2,200 cuyds of Elevation® geofoam Type 29. At 1/100th the weight of soil and compressive resistance at 10.9psi @ 1% deformation, it was the perfect solution for reducing weight and handling the heavy traffic and high axle weights allowed on Michigan highways.

Al Bosma, from Kamminga and Roodvoets, Inc. in Grand Rapids, Michigan, worked closely with Lisa Berryman, Atlas EPS Geofoam Specialist and project manager. The goal was to have the geofoam blocks delivered to the jobsite, as needed, so they were not exposed to the elements. This also minimized double-handling and the potential for damage to the blocks from construction traffic. The blocks were certified at the Atlas EPS plant on state-of-the-art testing equipment prior to each shipment so that Kamminga & Roodvoets was assured of receiving the highest-quality product even before the blocks arrived at the jobsite.

Due to the delay from redesign after the bridge shift, the project was not completed before winter set in. This did not prove to be a problem for Elevation® geofoam as the blocks can be installed in any weather. Expanded Polystyrene is susceptible to gasoline or diesel fuel and other hydrocarbons, so once the blocks were installed, a geomembrane was placed on top to protect them from this hazard.

MDOT has long recognized the benefits of using geofoam for settlement at bridge abutments and under roads. In 2010, MDOT used geofoam for seven different road projects. While geofoam has been used in European countries for lightweight structural fill for more than 40 years, the United States is just in the beginning stages of understanding the conditions where geofoam can benefit many state and federal road projects. Currently, there are approximately 35 states using geofoam for various transportation applications.

To learn more about Elevation® geofoam, contact Lisa Berryman, Atlas EPS Geofoam Specialist, at 616-889-5264. CEU presentations are available and can be tailored to your specific project. “Think Beyond the Block” and explore what Elevation® geofoam can do for your next project.