Thursday, 10 April 2014

Bridge Design

Fun practical session time!

We watched two Khan Academy videos produced by MIT - world famous technology college, I wish we could all go there - and loved
1. their clear explanations
2. their bridge inspiration and
3. their humour! :-)

Bridge Design and Destruction! (part 1): This is a two part video that introduces the different types of bridges. The bridge types will be introduced in historical order from simple (beam and arch) in the first video to more complex (truss and suspension) in the second video. This will show how bridges evolved as our designs and available materials expanded. The design of each bridge will be shown schematically along with the load distribution. The advantages and limitations of each type will be described. Video of actual bridges around Boston of the different types will be shown with the load distributions overlaid on freeze frames. Other iconic bridges will also be shown as still images with load distributions. Technical concepts covered will be tension, compression, bending, span, force balances, material selection and beam/cable design. License: Creative Commons BY-NC-SA More information at http://k12videos.mit.edu/terms-conditions
Bridge Design (and Destruction!) Part 2: This is a two part video that introduces the different types of bridges.


Then we split into four groups and practiced our own bridge construction.
 



Here are some things that we discovered:

1. Why cut when you can fold? A folded edge creates strength.
2. You can't block the flow of water when you are spanning a river!!
3. A bridge doesn't need to be pretty to be strong... but we all love pretty bridges...
4. Roads on bridges really should be horizontal for the poor cars. Even before the weight is put on them.

Cheating

Is it ever okay to cheat in sport?
This was a really neat discussion inspired by the situation which Valerie Adams had to face at the London 2012 Olympics - Ostupchuck beat her to the shot put gold by cheating.
 
We read an article written by Matt Harvey, who is of the opinion that cheating is a part of all sports - otherwise referees would be out of a job.
This inspired a lively discussion about whether it is a sportsperson's duty to her/his teammates to make sure that s/he works every angle s/he possibly can in order to score points against the other team.
 


Interested in the top 10 Sporting Cheats of all time? Here's a good one. Here's another - this is a mainly American list, but provides some interesting viewing. Note of course that none of these athletes every got away with it long term.