InTrans / Aug 14, 2018

Field performance of timber bridges: 5. Little Salmon Creek stress-laminated deck bridge

The Little Salmon Creek bridge was constructed in November 1988 on the Allegheny National Forest in Pennsylvania. The bridge is a simple span, single-lane, stress-laminated
deck superstructure that is approximately 26-ft long and 16-ft wide. The bridge is unique in that it is the first known stress-laminated timber bridge to be constructed of hardwood
lumber. The performance of the bridge was monitored continuously for approximately 4 years, beginning at the time of installation. Performance monitoring involved gathering and
evaluating data relative to the moisture content of the wood deck, the force level of stressing bars, the deck vertical creep, 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 field evaluations, the bridge is performing well with no structural deficiencies, although the bridge has developed a slight sag as a result of vertical creep.