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Spaghetti Bridge Experiment
We want the make a clever construction that is stronger than a single piece of spaghetti (or, a steel bar in the real thing). First, we need to know how much load a single one can carry before it breaks, and then compare it with our construction.
 We test the spaghetti pieces like this. Rest the piece on two supports and tie a weight to its centre (see picture). Have several weights ready with various masses, for example 10, 20, 50, 100, 250, 500 grammes etc., whatever you can find. Start with 10 g and with each next step increase the load by adding another weight. At each step measure how much the spaghetti bar has bent. The photos and the film make it clear how this is done. Put your measurements down in a table.
Carry on adding mass until the piece breaks. Now you know how strong one spaghetti piece is. If you want to do a really good job measure a few more pieces of spaghetti, to see if some are stronger or weaker than others. Make a note of the load that an average piece can support, for instance 12.7 grammes.
Experiment also with the distance between the supports. If they are too far apart the piece will bend and slip off before it breaks. But you will find that out soon enough.
If you set the supports closer you will find that the spaghetti can carry heavier loads. Make several tests with the supports, say, 15, 12, 9 and 6 cm apart. You will need these later when you compare the strength of your construction with the strengths of the single pieces.
Make some final tests with a bundle of spaghetti, e.g. five or ten. Find out that together they are indeed five or ten times stronger than a single one. Check also what happens if you glue them together. Are they now stronger or weaker?
Constructions
Let's have a look at real steel constructions, for instance railway bridges or crane arms. You will see they all are somehow put together as series of triangles.
 Try out different constructions by glueing together a few spaghetti. The best way to do this is to use a glue gun (see photo). This is an electric gun, which melts bars of plastic. When you apply it, the hot glue cools quickly and immediately binds two pieces together. No waiting.
Now find out why triangles are such clever things to build bridges and cranes with.
First, cut a number of spaghetti exactly the same length. You will need lots and lots of them. So, start making 50 pieces 5 cm long and 25 pieces 7 cm long. Or, if you plan to make a bigger bridge, 10 and 14 cm, respectively.
  Glue four 5-cm long pieces together to make a square. Make another square, now with a 7-cm long piece connecting opposite corners. Test both constructions by squeezing them in the direction of the arrows. You see that the square built of two triangles is much stronger. It doesn't even make much difference whether you press in the direction of the red or the green arrows.
Now for the real thing. If you connect a number of triangles you can make a beam that is strong and light at the same time. Like this:
Let's try out different constructions. There are different ways to make a bridge from a series of connected triangles. Here you see several examples, which we called, M-, W-, V- and inverted-V-constructions:
 A W-construction.
 A V-construction.
 An inverted-V-construction.
 The bundle bends and the pieces start breaking one after the other.
We found out that the best construction was the “M-construction”. This beam could carry the heaviest load of all our constructions: up to 400 grams! The construction took 17 spaghetti pieces. Now, 17 times the strength of one spaghetti would only be able to carry 160 grams of load. So, our construction is 2.5 times stronger than just the pieces it was made of! This was much better than we had expected.
We wanted to test a model of a bridge that you can walk on. So we created a simple bridge with two “M-constructions” with decks on top and at the bottom each of 10 bars glued together. For this bridge we used 28 whole spaghetti bars that separately would be able to carry around 0.64 kg. Some testing with the construction gave us 2.75 kg for the maximum load. This was more that the 2 x 0.64 = 1.30 kg we had expected.
 The bridge that Arie and Marc finally tested.
Here you can see a film of one of the tests we did:
 Click the picture to play the movie!
Now it is up to you! We are sure that you can create a bridge that can carry an even heavier load. Try making it lighter yet stronger than our bridge. You can start a contest with your friends or class mates.
Some tips:
 It makes a difference: apex up ur down!
- you can use sheets of lasagne for the bridge deck
 An arc bridge. Make your own bridge design and test its strength.
Who are Arie van Scheepen and Marc Luitjens?
Arie and Marc did these experiments for their high school final exam (Eerste Christelijk Lyceum, Haarlem, the Netherlands). Marc now studies astronomy at Leiden University. Arie wants to go to the film academy. Until that time, he works as an editor and sound engineer for Copernicus Journal for Young Scientists.
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I am doing spaghetti bridge for school and we are only aloud to use 1 packet of spaghetti (500g) and glue thats all and i am soooooo looking forward to it!!! 
and i came up with a gud design i think... 
SENIORS ROCK!
