>> LOL! OK, where's my latest Insight spam... OK, Autodesk AutoCAD LT 

>>
>> I'm *so* not trying that. :-P
> 
> There used to be a free version of ProEngineer called ProDesktop which 
> was really good.  Unfortunately they stopped that line for some reason, 
> and now there seems to be nothing available for home users in terms of 
> quality 3D CAD.

Well, I mean seriously, it's not like I'm DESIGNING AND BUILDING A PIPE 
ORGAN FOR MY HOUSE. [I'd just like to emphasize again that SOMEBODY 
ACTUALLY DID THIS.] I just like building stuff for fun. ;-)

>> I was chatting to some guy who apparently designs bridges and so 
>> forth. Maybe not "bridges" as such, but things like motorway flyovers, 
>> ramps, etc. Apparently it's kind of important to know about such 
>> things...
> 
> I would imagine so, you don't want a motorway flyover collapsing because 
> a queue of heavy trucks stops on it.  Also important to know how much 
> your bridge is going to expand/contract based on temperature and design 
> for that, otherwise you'll end up with a buckled road...

Well, when you see a huge bridge over the river Severn or something, 
it's obvious that some serious engineering went into it. But a small 
ramp up a hill? How hard could that be? Quite hard, apparently...

It still blows my mind that in some parts of MK, you drive down a road 
and there's a road crossing 30 feet below you, and a few yards later 
another road crossing 30 feet above you. And all of these roads are 
roughly level along their entire length, and level with the surrounding 
ground plane. That must have taken some *serious* hard-core earthworking 
to do in the first place...

>> Personally, I know very little about this kind of thing. Although I 
>> did read somewhere that at high speeds, materials behave as if they 
>> are harder and more brittle than they are. Which would explain why 
>> jumping belly-first into a pool of soft, liquid water is so God-damned 
>> painful. o_O
> 
> When you test the hardness of materials you generally apply the force 
> quite slowly, so can I well imagine that applying forces at a similar 
> speed to that which the material can deform will result in a seemingly 
> much harder material.  I suspect for things like road surfaces they 
> generally test with real life stuff and don't just go on the suppliers 
> hardness rating. Although you never know, when they built the Newbury 
> bypass they had to do it again a year later because the trucks had 
> ripped up the surface.

They were saying that if, say, a bullet hits things, they tend to 
shatter rather than deform. Apparently due to the velocity of the 
bullet, the materious "doesn't have time" to deform, so it shatters 
instead. Sounds pretty weird to me, but that's Wikipedia for you...

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