DESIGN, CONSTRUCTION, AND QUALITY CONTROL GUIDELINES FOR STRESS-LAMINATED TIMBER BRIDGE DECKS. FINAL REPORT

Under the U.S. National Timber Bridge Initiative Program, sponsored by Congress in 1989 and administered by the United States Department of Agriculture, Forest Service, approximately 130 modern timber bridges are currently in service in 41 participating States. Most of these bridges use stress-laminating technology. Considerable research on stress-laminating technology has been completed in the USA and has provided design, construction, and inspection guidelines for timber bridge decks. Guidelines for the design of stress-laminated timber decks have been published by AASHTO, but they do not provide comprehensive information on materials, construction, and inspection. Therefore, this document presents: (1) background information on timber bridge materials and their quality control; (2) a comprehensive step-by-step design procedure based on the 1991 AASHTO Guide Specification; and (3) guidelines for construction, field monitoring, inspection, and maintenance procedures. Potential fabrication problems are discussed, and an inspection checklist is included.