Sustainable bio-composites for highway infrastructure: Feasibility of material substitution in existing products

Abstract

The U.S, Forest Service regularly removes tons of dead biomass from federal forestlands to control and prevent devastating wildfires. Every year thinning young trees and brush, as well as removing dead biomass from the forest floor generates large quantities of low-grade woody material for which there is little use. Currently this biomass is either burned on-site, or at facilities to generate electricity. Finding a sustainable long-term utilization scheme for this material may generate a steady demand for this material and improve the economics of fire prevention. In this project the feasibility of substituting non-renewable materials currently used in a wide variety of highway infrastructure products, with sustainable composites utilizing low-grade woody biomass is investigated as potential alternative to burning. Devices such as traffic signs, road markers, and guardrails are installed on public roadways in high volumes. Until now, there have been no clear guidelines established for systematically assessing the viability of full or partial material substitution with more sustainable alternatives. A conceptual framework is presented, outlining necessary input information, inquiries, practical steps, and decision points necessary to determine if material substitution in a product or its individual components is viable. This procedure can assist entrepreneurs and small-scale businesses willing to enter the market, and provide opportunities in rural regions affected by the decline in the forest products industry. The application of this procedure is demonstrated on three selected highway products. Potential benefits to the environment, the economy, and local communities are discussed.