FHWA Resource Center
Structural Committee for Economic Fabrication (SCEF)
Modular Steel Bridges – Fast, Easy and Economical
Structural Committee for Economic Prefabrication
June 1, 2008
in conjunction with:
2008 International Bridge Conference
Portable Modular Steel Bridges got their start with the logging and mineral exploration industries. These activities required a heavy-duty bridge that could be easily moved around and installed, and support heavy off-road vehicle loads.
Big R Manufacturing, LLC pioneered one of the first Portable Modular Steel Bridge designs, over thirty-five years ago. This bridge product utilized two-beam modules with a corrugated deck, capable of supporting the direct application of a vehicles wheel load. These modules were fabricated in 20’ to 80’ spans, and were designed to set upon timber or precast concrete abutments. The typical wearing surfaces were either timber or gravel.
In the past decade, Big R Manufacturing, LLC has taken this concept and applied it to numerous permanent bridge installations. The modular concept allows for any width bridge crossing to be created. The wearing surfaces can still be wood or gravel, but more permanent asphalt and concrete overlays are becoming more popular.
This presentation will concentrate on the evolution of the Portable Modular Steel Bridge to the Permanent Steel Modular Bridge. It will show many of the features and benefits of modularization. In particular, the presentation will concentrate on a permanent bridge installation where the modular bridge concept was used. The modular bridge was first used as a temporary structure while the existing bridge was demolished. Then it was moved into place upon precast footings, supported by a backfilled steel Bolt-a-Bin abutment. Considerable time and money savings were achieved in this project.