It was like dozens of miniature re-enactments of the closing scene of the film The Bridge on the River Kwai Saturday at Porter Creek Secondary – minus the carnage and heartbreak. After all, these bridges were built to be destroyed.
About 70 Popsicle-stick bridges, including 16 entries from Dawson City’s Robert Service School, were pushed beyond their capacities at the 17th annual Yukon Bridge Building Contest hosted by the Association of Professional Engineers of Yukon.
Engineering enthusiasts built bridges to span a 700-millimetre gap, only to push the them to structural failure by incrementally adding weight to their mid section.
Although there is no limit to the number of Popsicle sticks a bridge builder could use, the weight of the structure is squared and then divided by the weight the bridge sustained before failing, placing more emphasis on efficiency than shear strength.
“We do that to encourage the kids to build an efficient design, not just a strong design, which is a key element to engineering,” said organizer and judge Catherine Harwood. “It’s actually more important how heavy your bridge is than how much it holds.
“The most points I’ve ever seen is 10,000, but the average for the winners is around 3,000 to 5,000. Ten thousand was a winner back when we had a smaller span; we used to have the testing stands 500 millimetres apart and now we have them 700-millimetres apart.”
Other specification for the bridges included having a solid deck at least 130 millimetres wide, not exceeding 30 centremetres in height or having a bottom section lower than 15 centimetres below the deck.
“There are constraints when you’re doing a design in real life, and one of them for a bridge is that it can carry vehicles,” said Harwood. “We’re trying to make it harder for them because they’re getting pretty darn good.”
After spending about two months constructing bridges out of two boxes of 10,000 sticks, Whitehorse Elementary student Danielle Lister was one of the day’s top winners, with structures finishing first and second in the Grade 4-5 division.
“You have to sort (the Popsicle sticks) because some are bent and stuff,” said Lister. “You have to look for the straight ones; the straight ones are the strong ones.
“Don’t use a lot of sticks because it adds a lot of weight. And wipe off the extra glue.”
Already a veteran of the competition, Lister has had strong results in past competitions, finishing second in Grade 3 and winning the ineligible division, for bridges that did not meet specification, last year.
“My dad designed the bridge when I was in Grade 3 and we came in second,” said Lister.
“I didn’t know what was wrong with it (last year) because we checked the rules.”
Finishing behind Lister in third was a team of Takhini Elementary students made up from Britteny Guindon, Hannah Stanley-Lyslo and Susie-Anne Cardinal.
The Grade 6-7 division was dominated by Takhini Elementary students, capturing 14 of the top 15 spots, topped by Ellysse Dunstan and Alysa Weins in first. Whitehorse Elementary’s Sam Bonar and Brendan Irish prevented Takhini from sweeping the top 15 spots by taking sixth.
Although spanning the most grades, the Grade 8-12 division consisted of just two entries, with Porter Creek Secondary’s Cameron Cottrell-Tribes taking first and Vanier Catholic Secondary’s Nick Kotun, Kamran Idrees and Mitch Young taking second.
“We don’t have as much interest in the high schools as we’d like,” said Harwood.
Taking first in the open final was Lister’s father, Jeff Lister, and Porter Creek Secondary’s Wayne Thomas came first in the ineligible division.
Top-10 results
Grade 4-5
1st Danielle Lister (WES)
2nd Danielle Lister (WES)
3rd Britteny Guindon/Hannah Stanley-Lyslo/Susie-Anne Cardinal (TES)
4th Gerold Stange (RSS)
5th Michael Betts (RSS)
6th Jesse Favron (RSS)
7th Emma Davis (RSS)
8th Connor Cottrell-Tribes (HVS)
9th Madison Betts (RSS)
10th Lulu Bartholomeus (RSS)
Grade 6-7
1st Ellysse Dunstan/Alysa Weins (TES)
2nd Chloe Slessor-Morrison (TES)
3rd Kimberley Dickson/Kessiah MacKenzie (TES)
4th Shelby Harper-Smarch/Emma Hoogland (TES)
5th Arianne Germain/Ashley Lai (TES)
6th Sam Bonar/Brendan Irish (WES)
7th Reanna Newsome/Mikayla Duncan (TES)
8th Brandon Lefler/Kyle Gonder/Scott Anderson (TES)
9th Paul Nikitiuk (TES)
10th Bruce Lemphers (TES)
Grade 8-12
1st Cameron Cottrell-Tribes (PCSS)
2nd Nick Kotun/Kamran Idrees/Mitch Young (VCSS)
Open
1st Jeff Lister
2nd Mike Tribes/Connor Cottrell-Tribes/Cameron Cottrell-Tribes
3rd Aidan Stoker/Al Loewen
4th Leah Smarch/Jane MacArthur (TES)
5th JD Caudle/Ben Barrett-Forest/Lara Bellon/Caroline Holoway (VCSS)
6th Aimee Lien (PCSS)
7th Ukjese van Kampen/Shasunjen van Kampen/Yaaya van Kampen
8th Taylor Harvey/Jordyn Cowan/Chad Cowan (WES)
9th Mallory Pigage (PCSS)
10th Jessica Pruden (PCSS)
Ineligible
1st Wayne Thomas (PCSS)
2nd Sidney Stewart (PCSS)
3rd Woo Jin Jung/Tristan Ledgerwood/Tristan McCallum/Scott Sumner (SES)
4th Tomas Jirousek (SES)
5th Anthony Andre/Logan O’Shea/Tyler Millwater/Bryan Fuentes (TES)
6th Colin Wilson (TES)
7th Madison Dixon/Jasmine Jobson (SES)
Contact Tom Patrick at tomp@yukon-news.com