InTrans / Aug 14, 2018

Field performance of timber bridges: 1. Teal River stress-laminated deck bridge

The Teal River bridge was constructed in late 1989 in Sawyer County, Wisconsin, as a part of the demonstration timber bridge program of the USDA Forest Service. The bridge is a stress-laminated deck structure with a 32.5-ft length and a 23.7-ft width. The design is unique in that it is the first known stress-laminated
timber bridge in the United States to be constructed of full-span glued-laminated timber beams, rather than the traditionally used sawn lumber laminations. The performance of the bridge was continuously monitored for 2 years, beginning at the time of installation. This performance monitoring involved gathering data relative to the moisture content of the wood deck, the force
level of stressing bars, the deck dead-load deflection, and the behavior of the bridge under static-load conditions. In addition, comprehensive visual inspections were conducted to assess the overall condition of the structure. Based on 2 years of field evaluations, the bridge is performing well with no structural or serviceability deficiencies.