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Research and Development (R&D) Project Sites

Project Information
Project ID:   FHWA-PROJ-08-0033
Project Name:   Wood Preservative Treatment Guide for Historic Covered Bridges
Project Status:   Completed
Start Date:  September 12, 2008
End Date:  September 30, 2013
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:   National Historic Covered Bridge Preservation Program
Project detail
Roadmap/Focus area(s):   Historic Preservation
Project Description:   Several studies have already been completed from the previous year’s research effort identifying preservative treatments, fumigants, fire retardant treatments, and remedial treatments: Identification of Preservative Treatments and Fumigants for Treating Historic Covered Bridges.Effect of fire retardant treatments on covered bridges.Remedial treatments for field treating timber bridges. These have been separate studies that need to be reviewed and relevant information extracted to produce a guide for engineers in selecting and treating timber members for these historic structures.
Goals:   The objective is to develop a guide identifying chemical wood preservatives for use by engineers and bridge preservationists that maintains historic integrity yet remain effective. 
Product Type:   Draft standard, specifications, or guidelines
Research report
Test Methodology:   Existing research reports will be evaluated and relevant materials extracted to produce a practical manual.
Other Information:   Funding is $100,000 (Federal Highway Administration) + $30,000 (Forest Service—Forest Products Laboratory).
Expected Benefits:   This project resulted in a guide to be used by bridge inspectors and preservationists for treating wooded structures against fungal attacks.
Deliverables: Name: Guidance on the selection and use of chemical wood preservatives for historic covered bridges.
Product Type(s): Research report, Techbrief, Draft standard, specifications, or guidelines
Description: This product will be a practical guide developed from years of field research identifying effective treatments that conform to historic preservation standards.
Publication URL(s):
FHWA Topics:   Roads and Bridges--Structures
TRT Terms:   Wooden Bridges
Wood Preservatives
Covered Bridges
FHWA Disciplines:   Structures
Subject Areas:   Bridges and other structures


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