Balsa Bridge
By Garrett Boon on May 25, 2006 - Modified April 20, 2011
This balsa bridge was built by some students of mine for a Science Olympiad competition. It spanned 14 inches, weighed 8.1 grams, and held 29 pounds. That puts its efficiency at 1630.
This photo makes the bridge look a little lopsided. That wasn’t the case, however.
Here is a photo of where the bridge broke. Click the picture to get a really good close-up.
Any tips for a first time builder Garret?
Hey John, I’d recommend for any first time builders to check out my “5 Steps to Building a Model Bridge” free ebook here:
http://www.garrettsbridges.com/design/5steps/
my bridges had a set of x’s on all side it held 60 piunds im in 8th g
i want to know how to make a standerd bridge with a with of 15cm and a lenght of 45cm.
how could they have made the bridge stronger?
do you have any tips on making our bridge lighter
we used a lot of bass wood and there happens to be a lot of extra glue on our bridge (…our fault.).
anyways…yeah
thanks!
anna k and lea
:]
hey garret do you know what science olympiad is?
Yep, I spent 7 years competing in SO, and these past few years keeping tabs on what’s been going down in the SO world.
i am a 7th grader and i have to build a bridge out of balsa wood and i have 20 ft of sticks to work with. how many feet was used for the 2nd bridge?
Garret can u tell me how tall and wide this bridge was
This bridge was 2 inches wide and 3 inches tall
how long was it and how long was the top part?
The bridge was just over 14 inches long, and the top flat part was 2 inches long.
Im an 8th grader and we are doing this project what do you think would be the lightest yet strongest bottom. Need to know soon!!!!!! Thanks
I’m looking for blueprints for a balsa bridge for my class prj where’d u find yours
sorry i haven’t been posting much lately been very busy at school with speech and debate.
No worries, I appreciate any time you spend here posting and answering questions.
The load was placed on top in the center of the bridge.
I am competing in a truss bridge building contest, and I’m not quite sure I understand where they put the weight. If the top of the bridge is covered, do they just put the weight there, or do they put it inside the bridge?
Ellie, I’m afraid I cannot answer your question. I have no idea where your bridge will be loaded. I’d ask the host of your contest, or refer to any rules/guidelines you were given.
I’m a science teacher and I’m considering having my 8th-graders doing a project like this. Where was the load placed on this bridge? I’m not sure I understand from the pictures.
hey i suggest you strengthen it with some wood wood is fairly strong and light also attatch the wood with a glue of some description
Say I wanted to build a bridge similar to this, except it will be elevated by two 10 cm columns.
How would you suggest I strengthen the base of the bridge without adding too much weight?