InTrans / Aug 14, 2018

Design, Construction, and Evaluation of Timber Bridge Constructed of Cottonwood Lumber

The Cooper Creek bridge was constructed February 1992 in the city of Centerville, Iowa. The bridge is a two-span continuous stress-laminated deck structure with a length of 12.8 m and a width of approximately 8.1 m. The bridge is unique in that it is one of the first known stresslaminated timber bridge applications to use eastern cottonwood lumber. The performance of the bridge was monitored
continuously for 28 months 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. On the basis of field evaluations, the bridge is performing well with no structural or serviceability deficiencies.