From Engineering Exposition

Contents 1 2010 Balsa Wood Bridge Competition 1.1 Competition Contact Information 1.2 Competition Deadlines 1.3 Award Categories 1.4 Construction Restrictions 1.5 Bridge Testing 1.6 Competition Committee Release Statement 2 Registration Form

2010 Balsa Wood Bridge Competition

Saturday, March 6th, 2010

TIME 1:00 PM

WS SPEED HALL 013

JB SPEED SCHOOL OF ENGINEERING

Competition Contact Information

• Richard Book
  • Community Outreach Director, ASCE/ASME Student Chapter
  • Civil & Environmental Engineering Department, University of Louisville
  • rabook01@louisville.edu
• Kenny Carrico
  • EExpo Coordinator, ASCE/SAME Student Chapter
  • Civil & Environmental Engineering Department, University of Louisville
  • jkcarr03@louisville.edu
• Mark McGinley, Ph. D.
  • Professor & Endowed Chair for Infrastructure Research
  • Civil & Environmental Engineering Department, University of Louisville
  • m.mcginley@louisville.edu

Competition Deadlines

Contestants must complete the Entry Registration Form (last page of this document) and submit, via e-mail, to Richard Book (rabook01@louisville.edu) by 12:00 Noon on Friday, February 19, 2010. The deadline for check-in on competition day is 11:00 A.M. at WS Speed Hall 013. Bridges will be weighed in and judged for best construction at that time. Please review the form (shown with example members) before completing with your team information. Make sure the primary e-mail address given will be checked daily for any notices or modifications send out by the Competition Committee.

Award Categories

• Best Performance Overall in Load Testing (1st / 2nd / 3rd place awards given)
• Best Construction / Visually Appealing (1st / 2nd / 3rd place awards given)

Construction Restrictions

1. Materials used in the construction of the bridge shall consist only of commercially available balsa wood stock and glue.
2. The bridge shall contain no element wider than 1.0 cm (3/8 ") nor thicker than 0.65 cm (1/4 ") Two or more elements, each separately meeting this requirement, may be laminated together to construct members exceeding these dimensions.
3. The bridge shall allow a 5.0 cm cube to pass through it along the span without touching the structure. The bridge must be at least 40 cm (16 in) long and no greater than 45 cm (18 in) long. For testing it will be placed on abutments that are 40 cm (16 in) apart.
4. The bridge shall be "free standing".
5. An approximately level, smooth roadway surface, of minimum length 40.0 cm and minimum clearance height of 5.0 cm, shall be provided, across which a small metal car (e.g. Matchbox, Hot Wheels) will roll when given a single light push of the hand. This roadway shall have a minimum clearance width of 5.0 cm and shall allow a 5.0 cm cube to pass freely along its extent. Note: the roadway materials must conform to rule (2).
6. No fastening mechanism except mechanical interlock of the balsa pieces or commercial glue is permitted.
7. The bridge design shall allow the standard test frame to be placed on the bridge with the load support rod(s) extending beyond the bridge sides.

Bridge Testing

1. The bridge pedestals shall be placed on level surfaces separated by approximately 40 cm (16 in). These surfaces shall be level with respect to each other.
2. The standard test frame will be placed on the roadway over the centre of the bridge span. Depending on the bridge design, the load applied to the bridge shall be at third points along the top chord of the bridge. The judges reserve the right to modify loading conditions if and when they see fit. The two following pictures illustrate a typical bridge testing setup. Notice thelocations of the load support rods with the loading frame resting on top of them.
3. The load will be applied by a universal testing machine at a slow, steady rate, until either an audible cracking sound together with visual evidence indicates the failure of some structural member or glue joint of the bridge, or until a suitable reference point on the roadway at the center of the span has been lowered by more than 1.0 cm. A competitor may not participate in the addition of weight to his/her own bridge.
4. The total mass of the test frame and applied load shall be divided by the structure weight to determine the score. A category will also exist for the best bridge with the best overall construction.

Competition Committee Release Statement

Note: All rulings made by the judging committee are final. Note: Any modifications to the design standards will be sent out to e-mail addresses given on the Entry Registration Form. No modifications will be made after Wednesday, February 24th, 2010.

Registration Form