OREGON STATE UNIVERSITY

Green buildings laboratory to boost sustainable construction

03/12/2009

CORVALLIS, Ore. – Imagine taking wood that’s soft and weak and using a combination of heat, steam and pressure to transform it into a product more than twice as strong as Douglas fir. And consider that this wood comes from trees that grow incredibly fast and thrive in the Pacific Northwest.

Such technology, experts say, may produce a new type of wood product industry in Oregon based on hybrid poplar – and nurtured by a new Green Buildings Material Testing Laboratory being set up at Oregon State University. It is one part of a new grant announced today from the Oregon Built Environment and Sustainable Technologies Center, or Oregon BEST.

“When hybrid poplar took off in the Pacific Northwest, it was envisioned that most of it would be used for pulp and paper,” said Fred Kamke, the JELD-WEN professor of wood science and engineering at OSU. “It’s a low-density wood with low strength. But we want to make it stronger, stiffer and harder, and able to compete for other uses that have a much higher value. And I think we can do that.”

Hybrid poplar trees can grow up to 12 feet a year and be produced in plantations much like an agricultural crop, but the wood itself is about 60 percent voided space. Researchers are using a technique called “viscoelastic thermal compression” that combines moisture, heat and mechanical compression to reduce that space, creating veneers that resemble hardwoods in their strength and density.

“Some of the first uses of this type of product might be as structural beams or perhaps wood flooring,” Kamke said. “Ultimately, these types of wood products could be so strong they might replace steel and concrete in some construction purposes.”

The new laboratory, Kamke said, will be very important in helping researchers to produce samples more quickly and efficiently, and test the results. A challenge in the near future will be to scale up what’s already working in the laboratory to commercial applications.

The new Green Building Materials Laboratory is a collaboration of OSU’s College of Engineering, College of Forestry, and one of Oregon BEST’s shared-use research facilities, and will be designed to serve as a showcase for green building in Oregon.

In the first year of the laboratory’s work, a high intensity concrete mixer is also envisioned, that incorporates non-traditional materials. Other initiatives are planned in future years as the laboratory evolves. An accelerated pavement testing machine will be constructed to more effectively analyze warm mix asphalt and “perpetual pavements,” which are types of sustainable asphalt pavement technology. Advanced fiber-reinforced composites can be created that will enhance new construction and help repair and lengthen the life of existing structures.

And as more of these renewable, bio-based materials become incorporated into buildings of the future, evaluation systems will be needed to assess the long-term effects of wetting, humidity, temperature cycles and exposure to biological agents. Toward that goal, an assessment facility for green building systems is envisioned, which will be able to simulate everything from ultraviolet light and humidity to wind-driven rain.