Design of Falls Creek Trail Bridge: A Fiber Reinforced Polymer Composite Bridge

Abstract

The need for lightweight, low-maintenance, easily constructed bridges for remote locations has existed for a long time. The backcountry of forests and parks throughout the United States is made accessible by trail systems that often encounter streams, rivers, gorges, and other features that must be spanned. Because of their remote locations, conventional approaches to spanning these barriers often are impractical. The Eastern Federal Lands Highway Division of FHWA, in conjunction with the United States Forest Service and with assistance from E.T. Techtonics, designed, tested, and constructed a pedestrian trail bridge 13.9 m (45.5 ft) long made of fiber reinforced polymer (FRP) composite members. Development of design procedures for this type of bridge is presented. The initial load testing results used to evaluate the analysis and design of the structure are presented and future construction plans for this bridge are mentioned. Attractive characteristics of FRP composites for construction of pedestrian trail bridges and shortcomings are illustrated. Further testing and research of the Falls Creek Trail bridge are ongoing and further testing and research of FRP composites also are needed. Advances in the understanding of currently available materials, as well as advances in the materials themselves, likely will affect structural design methods and procedures in the future. However, on the basis of available data, FRP composites appear to be well suited to meeting the need for backcountry trail bridges.