Design Examples

These glulam bridge design examples were generated through a joint venture agreement between the USDA Forest Products Laboratory (FPL) and Laminated Concepts Inc. (Big Flats, NY).  Another FPL publication, FPL-GTR-260 (PDF), is also available which includes detailed design information on glulam bridge designs.

A total of 4 different bridge superstructure designs are provided with step-by-step Mathcad design calculations. These glulam bridge designs all comply with the design requirements from the 2017 AASHTO-LRFD (8^th edition, including 2018 revisions) bridge design specifications.

1. Longitudinal Glulam Deck utilizing Douglas Fir (PDF)
2. Stress-laminated Glulam Deck utilizing Southern Yellow Pine Stringers (PDF)
3. Glulam Stringer with Transverse Glulam Deck utilizing Southern Yellow Pine (PDF)
4. Transverse Glulam Deck (Interconnected) utilizing Douglas Fir (PDF)

These designs are provided as an aid for the design process of the bridge superstructure.  With this information, engineers can save time in the design process.  A more complete set of design and construction drawings and specifications suitable for the bridge location should be developed under the supervision of a licensed professional engineer.

If you have comments or suggestions, please submit them here.

Short videos for each of these glulam bridge systems are available below and provide best practices for their construction tasks.