Archer Daniels Midland Yard Repair

Decatur, Illinois

Approximately 150 GeoSpike® elements were installed in a 280’ section in 2 days to solve subgrade issues in the rail yard. 

  • Owner: Archer Daniels Midland 
  • Geotechnical Engineer: SKS Engineers 
  • General Contractor: Archer Daniels Midland
Client's Challenge

Archer Daniels Midland (ADM) was looking for an alternative option to solve subgrade issues that are prevalent around the rail yard. An onsite inspection was performed focusing on a 280ft section of track having a history of surface defects and repeated maintenance. The site inspection revealed soft, wet subgrade conditions below the ballast that were indicated by mud pumping and soil bulging at the toe of the ballast line. Geotechnical investigation provided evidence of adequate bearing soils 8 feet below the ballast line.

Subsurface Conditions

The geotechnical challenges with this project related to the soft, wet subgrade underlying the ballast. ADM had been periodically addressing the issue by raising and tamping the subgrade every few months but wanted a more permanent solution.

Geopier® Solution

The Geopier®  solution for this project consisted of 6 ft GeoSpike® elements installed so that the GeoSpike apexes were 1-1.5 ft below the existing ties. The GeoSpike elements were installed in pairs spaced every other tie to resist a Cooper E-80 derived working load of 16 kips per GeoSpike. Approximately 150 GeoSpike elements were installed in the 280’ section in about 2 days using a rubber tire excavator with vibratory driver. The track was then resurfaced after the installation of the GeoSpike elements.

Geopier was able to work in-between trains and clear the track for traffic. The project was completed in conjunction with the switching operations with minimal impact on service and revenue.