Historic Glued-Laminated Arches Evaluated for Structural Quality


Building Two on the FPL campus was constructed in 1934 and deconstructed in 2010. Bottom photo credit: Steve Schmeiding, FPL.

The second glued-laminated structure built in the United States was constructed at the USDA Forest Products Laboratory (FPL) in Madison, Wis. “Building Two” was constructed in 1934 to demonstrate the performance of wooden arch buildings. At various times it acted as a supplementary laboratory, lecture hall, and storage facility. Building Two was decommissioned in 2010.

A new General Technical Report (FPL-GTR-226) by FPL engineer Doug Rammer and Jorge Daniel de Melo Moura of the Department of Architecture and Urbanization, Universidade Estadual de Londrina, in Parana, Brazil, details a systematic evaluation of the glued-laminated arches used to construct Building Two. Glued laminated timbers are a manufactured structural timber product composed of layers of dimensional lumber glued together.


Construction of Building Two in 1934 used three different glued laminated arch configurations. Click on the photo to view a larger version on the FPL Flickr site.

Shortly after the construction of Building Two, researchers evaluated the glued-laminated arch structure for uniform loading on the center arch. This structural system evaluation was added to the existing laboratory work on glued-laminated arches to develop the foundation on which the current glued-laminated arch design criteria is based.

After decommissioning, recovered arches were tested in the Engineering Mechanics and Remote Sensing Laboratory at FPL to evaluate the loss of structural performance by comparing original and current deformation. Based on a preliminary visual and structural assessment Rammer and Melo Moura found minimal loss of structural performance in all the arches but one, an arch that was exposed to a significant amount of water resulting from extinguishing a fire in Building Two.