Guardrail Post Possibilites: A New Use for Forest Thinnings?

Small-diameter trees can be used for a variety of products, including lumber, structural round wood, wood composites, wood fiber products, compost, mulch, energy, and fuels.

Developing even more uses for small-diameter trees would increase their product potential, encouraging thinning projects that remove trees from overcrowded forests, thereby improving forest health and decreasing the risk of catastrophic wildfires.

Rigid nose steel-framed test vehicle for guardrail post tests.

Rigid nose steel-framed test vehicle for guardrail post tests.

In response to this need, Forest Products Laboratory researchers and their partners at the Midwest Roadside Safety Facility at the University of Nebraska-Lincoln are studying using small-diameter wood for highway guardrail posts.

Currently in phase two, the study has already determined appropriate sizes of southern yellow pine, Douglas-fir, and ponderosa pine round posts for use in the 31-inch-tall Midwest Guardrail System. Now researchers are looking to continue to expand opportunities for using round ponderosa pine in guardrail systems as a substitute for the rectangular southern yellow pine posts commonly used.

The Midwest Roadside Safety Facility will conduct low-speed, dynamic component tests on nine round ponderosa pine posts and three rectangular southern yellow pine posts set in a compacted, crushed limestone soil material. Each test will be performed at a speed of 15-20 miles per hour using a rigid nose, steel-framed reusable test vehicle.

Results of this research program are expected to provide test results that allow round ponderosa pine posts to be substituted into existing U.S. highway guardrail systems.

Further information is available in this Research in Progress report.

Example of dynamically tested ponderosa pine post.

Example of dynamically tested ponderosa pine post.