InTrans / Aug 14, 2018
Field performance of timber bridges: 19. North Yarmouth stress-laminated truss bridge
The North Yarmouth bridge was constructed in the spring of 1994 in North Yarmouth, Maine. The bridge is a single-span, two-lane, stress-laminated truss structure that is approximately 39 ft long and 32 ft wide. The truss laminations were produced using chromated-copper-arsenate- (CCA-) treated Southern Pine connected with metal plate connectors. This report includes information on the design, construction, and field performance of the bridge. Performance of the bridge was monitored for approximately 4 years, beginning shortly after bridge construction. During the field-monitoring program, data were collected related to the wood moisture content, the force level of the stressing bars, behavior under static truck loading, and overall structural condition. Based on 4 years of field evaluations, the bridge is performing well with no structural or serviceability deficiencies.