By: Big R Bridge
Big R Bridge was approached by engineers to help them build a structure that could support an E80 Cooper train loading with less than 4ft of cover. After reviewing the details of the project Big R decided that a deep corrugated box structure was the way to go.
After construction, the flexible buried bridge supports a loop track and spans the main entrance road to Central Valley Agricultural Cooperative. This is the longest span box culvert in the US supporting rail loading. Although it is usually not recommended for buried structures, the engineer opted to support the 
structure with deep foundations. This limited settlement while foundation soils below the backfill zone were allowed to settle and, because of the resilience of the flexible structure, there were no adverse effects. The structure included precast panel MSE headwalls and wingwalls to limit the structure length and provide a landmark feature as an entrance to the facility.
As a result of this project, deep corrugated box structures are becoming more common as an alternative to precast concrete and traditional bridges in grade separation and hydraulic applications on rail projects.
For more information on this project visit Big R Bridge’s website here.