CNRR St Charles Line Bridges
scope of work
- Low Clearance Micropile Drilling
- 210 Micropiles Installed
- Multiple Micropile Tests
- 70 Soldier Piles Installed
- 20+ Tiebacks Installed
- Excavation Over 20' Next to Active Tracks
The project consisted of the complete replacement of the Chicago CN Bridges over Dearborn, Michigan, Wabash, and State. This project was done in two phases to maintain one active track at all times. Our work included the stage line earth retention to support a 20ft excavation for the new cast in place abutment. The excavation supported an active train right adjacent to the work. After the earth retention was installed, micropiles were drilled as foundation for the new bridge.
This process was repeated at 3 bridges. Dearborn was slightly different where the bridge was supported with wedding cake foundation footings. The existing footing were replaced with footings supported on micropiles. Due to the staging, the micropiles had to be installed using a low- clearance drill under the existing bridge.