Field performance of timber bridges. 7, Connell Lake stress-laminated deck bridge

Abstract

The Connell Lake bridge was constructed in early 1991 on the Tongass National Forest, Alaska, as a demonstration bridge under the Timber Bridge Initiative. The bridge is a stress-laminated deck structure with an approximate 36-ft length and 18-ft width and is the first known stress-laminated timber bridge constructed in Alaska. Performance of the bridge was monitored for 2-1/2 years, beginning at bridge construction. Performance monitoring involved gathering and evaluating data relative to the moisture content of the wood deck, the force level of the stressing bars, and the deflection under static load. In addition, comprehensive visual inspections were conducted to assess the overall condition of the structure. Based on 2-1/2 years of field evaluations, the deck is performing well with no structural deficiencies. However, a slight sag has developed at midspan and several stressing bar bearing plates have crushed into the outside deck laminations.

Citation

Hislop, L. E.; Ritter, M. A. Field performance of timber bridges. 7, Connell Lake stress-laminated deck bridge. (Research paper FPL ; RP-550):13 p. : ill., maps ; 28 cm.