engineering

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engineering

Postby raymajoros » Mon Jan 21, 2013 6:19 pm

how should i go about building a bridge out of popsicle sticks? what do you think the best way to test the strength of the bridge against others is?
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Project Question: Which bridge design can hold the most weight; the truss, cantilever or the beam bridge. Can we invent a stronger design?
Project Due Date: 1/25/13
Project Status: I am conducting my research

Re: engineering

Postby kgudger » Mon Jan 21, 2013 9:27 pm

Hello and welcome to the forums:

Have you reviewed the ScienceBuddies project? http://www.sciencebuddies.org/science-fair-projects/project_ideas/CE_p011.shtml#summary
The biggest problem with bridge projects is reproducing the results. I've seen dozens of these projects, and most of them are poorly done because they only test one or two bridges of each type. The results have little meaning in this case. If you can set up your experiment to test 5-10 sections of each type of bridge (maybe smaller sections so you can make more of them?) you will get more meaningful results.

Keith
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Re: engineering

Postby Craig_Bridge » Thu Jan 24, 2013 6:20 pm

Engineering projects are ususally judged against some defined "cost function". In the case of jobs that go out for bid, there is a set of requirements and the bids are evaluated based on cost and other factors called out in the requirement documents.

If you are doing the project without any external requirements, you get to choose the cost function and the requirements.

Many classroom competitions are evaluated using a cost function that involves the ratio of the failure weight to the weight of the structure for a given span requirement and a specified load plate that will be placed on the bridge to suspend the test weights from. In other words, a well defined set of requirements.
-Craig
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