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Research and Development (R&D) Project Sites

Project Information
Project ID:   FHWA-PROJ-06-0021
Project Name:   Structural Use of Wood-Plastic Composites in Transportation Applications
Project Status:   Completed
Start Date:  September 15, 2006
End Date:  September 30, 2011
Contact Information
Last Name:  Duwadi
First Name:  Sheila R
Telephone:  202-493-3106
E-mail:  sheila.duwadi@dot.gov
Office:   Office of Infrastructure Research and Development
Team:   Hazard Mitigation Team [HRDI-50]
Program:   Wood Composite
Project detail
Roadmap/Focus area(s):   Infrastructure Research and Technology Strategic Plan and Roadmap
Project Description:   The commercial manufacture of extruded wood-plastic composite (WPC) materials is well established in the United States and Canada with the largest percentage of product output being comprised of exterior decking and railing systems. Currently, there are other specialty products being produced by extrusion and/or injection molding, which include roof shingles, molding, decorative post caps, and fencing. A well-perceived need in the industry is the production of wood-plastic composite (WPC) materials for structural applications. Potential structural applications include material components for pier and pilings, bridges, retaining walls, and foundation elements. Material formulations for wood-plastic composites typically contain 40 to 60 percent wood flour by weight, 30 to 50 percent polymer, and 5 to 10 percent additives. Transitioning WPCs into structural uses will involve research into extrusion of larger profile sections, hybridization with synthetic fiber reinforced polymer materials, understanding durability of the products in exterior load carrying applications, demonstrating the structural WPC products in real-world applications, code development, and design standards for structural WPC materials. Only limited research has addressed the structural application of WPCs so far. Great potential exists for structural uses of WPCs in transportation applications based on the perceived success of these products in residential and commercial construction. However, fundamental research is needed to affect the structural application of WPCs.
Goals:   The key project objective is to conduct fundamental research investigating the structural use of extruded wood-plastic composite materials for transportation applications.
Product Type:   Research report
Test Methodology:   The objectives will be accomplished through experimental and field research in the following areas: (a) Extrusion processing and reinforcement research. (b) Wood-plastic composite durability for structural applications, demonstration projects, and structural design criteria. (c) Code development.
Expected Benefits:   This project developed a new material for highway applications such as noisewalls, retaining wall and for bridge abutments.
Deliverables: Name: Feasibility Study on Wood-Plastic Composites for Transportation Applications
Product Type(s): Research report, Techbrief
Description: The deliverable will describe the research conducted to develop wood-plastic composite material for transportation and the demonstration project, and recommend its feasibility for further use.
FHWA Topics:   Research/Technologies--FHWA Research and Technology
TRT Terms:   Composite Materials
FHWA Disciplines:   Structures
Subject Areas:   Bridges and other structures


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