(Photo 1)Return to Honors Physics Home Page
Revised 01-19-06
Bridge building Competition
The 2006 bridge efficiency grading scale is located at the bottom of this page.
The Bridge building Competition is a mandatory part of Honors Physics, and upon completion, earns the student a double test grade for the second quarter.
Specific details pertinent to the 2002 Bridge Building Contest, will be given to you in class, sometime in October, when the International Committee formulates this year's regulations.
For additional information on designing balsa bridges, scroll to the bottom of this page and click on each of the links listed.
Illinois Institute of Technology's Bridge Building Contest Home Page.
Historical Notes: The 23d International Bridge Building Contest was sponsored by our regional committee at Montage Mountain Ski Resort in May of 2000.
Once you click on the address above, click on "2002 International Contest Information", which will allow you to click "2002 International Bridge Specifications". These specifications give you an idea what rules bridge building competitors all over the world have to follow, to qualify during their local competition, their regional competition, and finally at this year's international meet, which will be held in the state of Washington. Also, while on the home page, click on "Pictures of Past Contests", which shows the general method for testing bridges. The setup we use for our local contest at Abington Heights (which is held in early January) is very similar to the apparatus use during the regional contest (which is held on Saturday, February 9, at the Viewmont Mall). Mr. Donald Kieffer, a retired physics teacher from Abington Heights who teaches part-time at Scranton Prep, developed the apparatus design we use during the regional meet (Photo 1)
(Photo 1)
The photograph above shows the apparatus in profile. Your bridge will be placed across two parallel planks which run the length of the apparatus (you can only see the nearest plank to you). The bridge will be elevated on the red pieces of wood, facing outward from this photo. A metal loading plate is inserted onto the bed of the bridge and a cable is attached to the plate and to the pivoted horizontal metal pipe below. The system is stabilized, so no measurable force is initially exerted against your bridge. The black box attached to the right end of the pipe is a Vernier force sensor, which is connected to a computer. Once you begin to add sand to the pail, the pipe begins to move downward, and the cable attached to the pipe and loading plate puts a downward-directed force on your bridge. Your bridge, in effect, is experiencing an ever-increasing load, which is recorded on the computer. The bridge inevitably collapses, and the ratio between the maximum applied load over the mass of the bridge gives your bridge's "efficiency". An efficiency of 2000 or better is usually required to place in the top three positions at the regional competition
While you are visiting the Illinois Institute of Technology's Bridge Building Contest Home Page, scroll to the bottom of the page, and click on "Other Bridge Links". This will take you to the "Bridge-Related Links" page. Click on "bechtel.com/building Minds/spanGame.html. This site offers the challenging bridge building game, "Span It". You will probably have to download the Shockwave plug-in onto your computer first, which takes about 7 minutes. Play the game!
West Point Military Academy is developing an interactive bridge building site for instruction and on-line competition. While the contest is not scheduled for a year, and the site is not fully functional, it offers sophisticated mathematical procedures for determining the load expectation for each strut member in a bridge. In order to view the procedures, you must down load the necessary software, which only takes a few minutes. Go to http://www.dean.usma.edu/bridgecontest/
Check out: http://www.ndrs.org/physicsonline/index.htm
http://www.howstuffworks.com/bridge1.htm
http://www.brad.ac.uk/acad/civeng/marketing/civeng/game2.htm
http://eduscapes.com/42explore/bridge.htm
http://www.mat.uc.pt/~pedro/ncientificos/artigos/techbal.html
http://www.jhu.edu/~virtlab/bridge/truss.htm
http://www.pitsco.com/p/CCbridges.htm
Bridge Efficiency Grading Scale - 2006:
Honors Physics students must submit their bridge by January 20, 2006 for inspection. Each bridge must meet criteria, which have been made available on line since October, before being qualified for formal testing. Any bridge that does not satisfy each of these criteria will be returned to the student, and the student may make final adjustments to the bridge, before having it rechecked. THERE WILL BE A REDUCTION IN GRADE FOR ANY BRIDGE NEEDING A SECOND INSPECTION. All bridges that fail the first inspection must be resubmitted by the next school day. Any bridge that fails the second inspection will earn a double grade no higher than 50%. No bridge will be accepted after January 20 for initial inspection, and two test-equivalent grades of 0% will be recorded.
All students will receive a double test-equivalent grade for the bridge building project, based on their bridge's efficiency. Students earning the top three efficiencies will receive a third grade of 105%.
Any Honors Physics student who has taken the effort to construct and test at least three practice bridges in room 511, prior to the actual submission deadline, MIGHT be given special consideration on the grade earned. The practice bridges must have met the basic design rules as stated on the 2006 International Bridge Building Contest document. These students have taken a significant amount of personal time in school to discuss, then engineer improvements in their bridge design. Extra consideration applied toward earning the required double-test project grade only (not as a qualified efficiency toward earning a position at the Regional Bridge Building Contest on February 11) will be as follows:
Number of Practice Bridges Built - Consideration
3 - may replace the 3d top practice efficiency with that earned on test day
4, 5, or 6 - may replace the 2nd top practice efficiency with that earned on test day
7 or 8 - may replace the top practice efficiency with that earned on test day, or a third grade of 100%
2006 Abington Heights Honors Physics Bridge Building Contest Grading Scale:
Efficiency - % Grade
3000 or better - 105
2900 - 105
2800 - 104
2700 - 104
2600 - 103
2500 - 102
2400 - 101
2300 - 100
2200 - 98
2100 - 97
2000 - 95
1900 - 94
1800 - 92
1700 - 91
1600 - 89
1500 - 87
1400 - 86
1300 - 84
1200 - 83
1100 - 81
1000 - 80
900 - 78
800 - 77
700 - 75