Timber bridge initiatives in the United States

Timber has been used for bridge construction in the United States for hundreds of years. Despite the proven suitability of timber for short- and medium- span bridges, its use as a bridge material has declined in the 20th century. This has been due in part to a lag in the development of new timber bridge technology compared to other materials, and an unfamiliarity with timber on the part of many bridge designers and contractors. Since 1988, two legislative acts have been passed by the US Congress to establish national programs aimed at improving timber utilization in transportation structures. This paper briefly describes these timber bridge initiatives and summarizes activities in the areas of demonstration bridges, research and development, and technology transfer.