General Chat / Popsicle sticks bridge school project

I have to make the strongest bridge for my physic class, and I'm not sure about the type of bridge I should go for...

Anyone have an idea?

Whatever it is, cover in completely in wood glue.

Ok...

http://en.wikipedia.org/wiki/Bridge
http://en.wikipedia....lsa_wood_bridge

Good luck!

A suspension bridge sounds good.

it's more or less the way you construct it. use triangles. and make sure to know where the load is applied so you can check for zero force members in your design before you build it and use less popsicle sticks on those.

A suspension bridge sounds good.

Make it like this one.
http://home.san.rr.c...es/image007.jpg

Too bad he's making it out of popsicle sticks.

pB: thanks for this one advice. less sticks on the parts which have no tension. I'll try that.

Suspension bridge wouldn't work, sticks can't replace cables. it doesn't have the "elastic" attribute that have the cable. Pression would go up and the sticks would brake in half.

MachChunk: hum... esthetism is also important.

Thanks all.

Just make a basic truss bridge. Use as many cross beams and triangles as possible. The cover the thing in glue. That gave mine in 8th grade some good strength. As much as it sucked, middle school was good for things like this...

-Rct2123

Do you get bonus points if you use the fewest popcicle sticks? If not, then get a little creative, but like P.Bob and RCT2123 said, use plenty of triangles. (There probably the best shape in all of mankind.) I would personally go with an arch bridge, actually. Make the arches large, and use plenty of glue. The Romans made spectacular stuctures with arches and cement, although they didn't exactly have 1 ton automobiles either...

So, you can only use popsicle sticks? Hmm. I'd have to concur with the general idea of triangle bridges.

The "resistance" points are counted this way :

The weight you put on the bridge/ weight of the bridge

Something like this.

For the archway, just turn the popsicle sticks on their side.

Actually, do that for the entire bridge. Turn all of the sticks sideways so that they'll be able to take the most load for the least amount of weight. [see what I'm getting at?]

This works well, too.

Edited by Rhynos, 24 November 2007 - 10:43 AM.

I'm not sure how I could do a perfect archway with popsicle sticks... and I don't think it would work, because there is no contact with the ground allowed on the side of the bridge in the contest...

The arch would just break up on the sides... It would be very weak.

Triangles is the way to go. But are you sure about the glue covering part?

EDIT: Exactly the bridge I want to build (second one). thanks.

Edited by lucas92, 24 November 2007 - 10:53 AM.

Weight was factored in for me too, but I still covered it in glue. It worked seeing as that it held over 100 pounds...

-Rct2123

Edited by rct2123, 24 November 2007 - 02:34 PM.

Oh, and glue multiple sticks together; that way, they won't bend out. And if I remember my prof's lesson, the strength goes up exponentially - especially with the glue.

OH!! USE RESIN!! NOT WOOD GLUE!! Seriously, they use resin to construct entire sections on highways (or at least to put hanging sections together).

And while I'm thinking of it, why not put 4 sticks together so they look like a straw (with a hollow center) then fill the center with resin! Can you do that? Can you use resin? If you don't have resin, epoxy it. Just be careful.

Depends on where you're applying the weight. arch bridge seems to work the best. Like a C with the open end facing downward, and the tips resting on the table. But really, just glue the shit out of it. I saw a kid design a bridge in CAD and build it professionally, and saw it lose to kid who just glued a bunch of sticks in a similar design similar design. Truss bridges tend to snap in the middle with length, where as the arch bridges hold up pretty well with decent construction (ours always snapped side to side when the weights shifted.).

don't put the arch under neath. Kind of like this shape: |(. you kant be sure that there will be walls to brace it against. What's to say the competition wont be between two student desks with nothing underneath?


(For our competition, the design had to be under a certain weight, couldnt drop below a certain height on the table, and couldnt use shit like epoxy.)

search for a program called Bridge Builder (Pontifex) and practice with that program.