PROJECTS OF CFC - TIMBER
West Virginia, which has an abundant supply of inexpensive timber, has become a leader in the construction of new timber bridges. The Constructed Facilities Center, in cooperation with the West Virginia Division of Highways, has been a major contributor to West Virginia's leadership in timber bridge construction and an active participant in the Timber Bridge Initiative of U.S. Department of Agriculture-Forest Service.
Modern timber bridges built in West Virginia are dramatically different from the 20th century ancestors. Meeting the demands of today's heavy traffic with the smaller timbers produced require a completely new way of re-engineering of timber bridge design.
Joining small pieces of timber together to form large structures such as bridges can be a big problem. Engineered wood products are the solution to many of today's construction needs. One form of engineered wood, which has been the major area of interest at the CFC, is known as stress-lamination. In addition, new stress-laminated timber deck systems, with stressing parallel to traffic flow, stiffened with steel wide flange beams, and are being implemented in West Virginia for higher traffic, volume and load intensity. Another engineered wood product that CFC is researching for bridge implementation is Parallam®, manufactured in West Virginia. Several bridges are being built in the state using the Parallam® deck on steel stringer after creosote treatment.
Working with engineers at the WVDOH and the USDA FPL, we have refined and advanced this new technology. In 15 years, more than 120 new timber bridges have been constructed across West Virginia. We are developing new repair techniques especially for covered (timber) bridges using modern adhesives and glass fiber reinforced polymer components. This work is being carried out in cooperation with the Institute for the History of Technology and Industrial Archeology at WVU and supported by USDOT-FHWA. New crash-tested guide rail systems suitable for timber bridges have also been developed through a joint CFC-FHWA project. The success of these projects illustrate that the capabilities of an old material can be used in new ways and more importantly, that a joint academic-industry-government team can have an immediate impact on a problem shared by all.