Research Project

Field Testing and Evaluation of a Demonstration Timber Bridge

Completed demonstration timber bridge

Researcher(s)

Principal investigator: Brent Phares, 515-294-5879, bphares@iastate.edu (project list)

Co-principal investigators:

Travis Hosteng, 515-294-7197, hosteng@hotmail.com (project list)

Project status

Completed

Start date: 11/15/08
End date: 12/31/11

Publications

Report: February 2012, Field Testing and Evaluation of a Demonstration Timber Bridge 2.64 mb (*pdf)

Related publications: Field Testing and Evaluation of a Demonstration Timber Bridge 2.18 mb *pdf (Tech transfer summary) February 2012

*To read pdf files, you may need to download the free Adobe Acrobat Reader.

Sponsor(s)/partner(s)

Sponsor(s):Iowa Department of Transportation
Iowa Highway Research Board

About the research

Abstract:

Asphalt wearing surfaces are commonly used on timber bridges with transverse glued-laminated deck panel systems to help protect the timber components. However, poor performance of these asphalt wearing surfacesin the past has resulted in repeated repair and increased maintenance costs.

This report describes the field demonstration and testing of a newly-constructed, glued-laminated timber girder bridge. Previous field work revealed that differential panel deflections in the glued-laminated deck were one significant factor resulting in the premature failure of the asphalt wearing surfaces on these bridges. In addition, laboratory work subsequent to the field testing attempted to address the problematic asphalt cracking common in transverse glued-laminated panel decks by testing several deck joint connection alternatives.

The field demonstration project described in this report showcases the retrofit detail that was determined to provide the best field performance. The project was a cooperative effort between the Bridge Engineering Center (BEC) at Iowa State University and the United States Department of Agriculture (USDA) Forest Service Forest Products Laboratory (FPL).

2711 S. Loop Drive, Suite 4700, Ames, Iowa 50010-8664
Phone: 515-294-9501 ~ Fax: 515-294-0467
The Bridge Engineering Center is administered by Iowa State University's Institute for Transportation.