NEWS from Southwest MS Resource Conservation & Development (RC&D), Inc.

PO Box 3670   Brookhaven, MS  39603-7670

601-833-5539   Fax 601-835-0054   E-mail southwest@msrcd.org

 

For more information contact Bennie Hutchins, RC&D Coordinator

___________________________________________________________________

16TH NATIONAL TIMBER BRIDGE DESIGN COMPETITION RESULTS ANNOUNCED

 

Sixteen teams of students from universities across the US matched wits in the recently completed 2008 National Timber Bridge Design Competition.  Open to student chapters of American Society of Civil Engineers (ASCE) and Forest Products Society (FPS), the competition was made possible by a grant from the US Forest Service through its Wood in Transportation Program.  Additional financial support was provided by Unit Structures LLC.  Southwest Mississippi Resource Conservation and Development (RC&D), Inc., coordinates the annual competition. 

 

Each team designed, constructed and tested their bridges on their home campus, then submitted documentation of their activities and results to a panel of judges for review.  The competition is conducted online via the Internet.  Each team is required to post design drawings, test results, and project highlights on the web at www.msrcd.org.

 

Winner of the Best Overall Design Award was Clarkson University ASCE. Their design consisted of two I-Beam Girders with 26 transverse floor beams integrated into the top flanges on 6.5-inch centers, then topped with a longitudinal deck of 5/4-inch x 6-inch southern yellow pine.  This entry also placed first in Best Deck, and second in both Best Support Structure and Most Innovative Design. The team received cash awards totaling $1,750 for their efforts.

 

The second highest money winner was the entry by ASCE-Team 2 from the University of Missouri at Columbia, taking home $1,200 in prizes. Their entry placed second in both Best Overall Design and Best Deck, and third in both Most Innovative and Most Practical. Their design consisted of five I-Beams with the top flange being the deck of Southern Yellow Pine 1 x 4 laminated on vertical axis with nine 5/8-inch diameter steel tension rods and fiberglass composite weave added for additional stiffness.

 

ASCE-Team 6, also from the University of Missouri at Columbia, was another big winner, taking first place in both Best Support Structure and Most Innovative. Their entry used five I-Beams to support a 1.25-inch transverse laminated deck.  The other first-place winner was ASCE-Team 1 from Oklahoma State University, winning first place in both Most Practical and Most Aesthetic for their laminated arch truss bridge with transverse decking.

 

Additional entries in the 2008 Competition included teams from Ohio State University, Oregon State University (2 teams), University of Tennessee at Martin, San Francisco State University (2 teams), University of Massachusetts at Amherst, University of Arkansas at Little Rock (FPS), University of Texas at San Antonio, U.S. Military Academy, University at Buffalo and a second team from Oklahoma State University.

 

For a complete review of 2008 Competition Results and each individual entry including drawings and photos, go to www.msrcd.org/bridge.htm and select from menu. Results of 1998-2007 competitions are also posted online. The status of the 2009 competition is still in doubt due to close-out of the federal Wood in Transportation Program that has provided major funding.  Sponsors from private wood products and engineering entities will be needed to keep the Competition going.  Interested sponsors are strongly encouraged to contact the competition coordinators immediately at southwest@msrcd.org or 601-833-5539.

 

The test bridges were 13 feet (4 m) long and 4.25 feet (1.3 m) wide and were loaded with a test weight of approximately 4,500 pounds. Average weight of the bridge models was 1,269 pounds (577 kg). At full loading, maximum bridge deflection ranged from 1.69 mm to 9.96 mm. Maximum allowable deflection was 10 mm. Percent non-wood materials in the bridges averaged 6.3%; maximum percent non-wood materials allowed was 25 percent, by weight.  All wood members were required to be treated to AWPA standards for ground-contact.

 

The competition's objectives are to promote interest in the use of wood as a competitive bridge construction material, to generate innovative and cost-effective timber bridge design techniques, and to develop an appreciation of the engineering capabilities of wood among future transportation and forest products engineers. Following the competition, most of the bridges were placed into use as trail or park bridges.