Sustainable Bridge Design
Well, Mark Yashinsky, webmaster of the Bridge photo of the Day (and noted author of books on seismic bridge design) sent me a river bridge concept!
(On a related note, I was asked to lunch by the department chair of our engineering department. Seems he is also a fan of sketchup or maybe he wants to fire me in a public place!)
Thanks Mark for entering! Next time I have a competition I will have to have prizes!
I took 15 minutes and drew a long span slab bridge (My deck is 2 feet thick.). I read the Happy Pontist article on granite slab bridges and I wondered how long and thin you could make a concrete slab with some prestressing strands. (concrete has a weight about 150 lb /cu.ft while granite is around 165 lbs/cu. ft.)
You can manufacture 30,000 psi concrete (expensive) and it should be more uniform and just as long lasting as granite. (Maybe? I would be worried the granite is not uniform in strength over its length.)
Anyway this is a “quick” play bridge. I am thinking I will have to make prizes if I have a bridge competition…
I am sitting around while another student has a go at my first exam. So I thought I would post a River Bridge competition for myself and anybody else who is bored…
I drew up a quick sketchup river section with two concrete abutments. The abutments are spaced 110′ feet apart on center and would accomadate a 10′ wide pedestrian bridge. (I wanted a quick template to try out some bridge ideas.)
If you draw something up, send me a jpg and I will post it with credit. Sketchup file here.
It needed a houseboat…
I put together a list of top bridge engineers about eight months ago. I am thinking about updating it with the top ten still alive bridge engineers?
Suggestions?
I thought I would throw out some names from the web, to get started. ( in no particular order.)
Updated: The Happy Pontist has suggested some more prominent bridge engineers for my list. I have to admit (sheepishly) that I don’t know many of them…but I am learning! The list with random links for each engineer.
Concepts for the replacement of the Kosciuszko Bridge on the Brooklyn-Queens Expressway.
From my quick survey of the room I think everybody is using a TI calculator. Nobody seems to have the George Bush or HP calculator. (Ya know expensive and does math backwards, HA!, thats right I said it.) I’
m getting loopy.
Seriously is a TI calculator really worth a $160 bucks? (about two euros or kilo-dollars) I used to program my calculator with buckling formulas and I even bought the Ti Voyage, which broke down in three months.
I have a grad student helper here and he thought he found a mistake in my exam! Yikes too late to change it. Frantic computering ensues…
Not to worry false alarm, me and STAAD check out….
I am sitting in a large windowless classroom as 63 students take a two hour structural analysis test Although it is -10 outisde it is +80 inside. (415 C to you metric types. You think your sooo cool with your kilo this and centi that, who really needs a worldwide standard anyway. Who says we need to design to a millimeter and not 1/16″. It was good enough for the Viking/pilgrams and it is good enough for me. Whoa sorry I getting heatstroke here..)
So I have to have a question and here it is, how do you design a test that gives the majority a chance to pass while challenging the keeners. (Canadian term for cool guys or was that nerds?) AND a test the course leader doesn’t hate and eventually uses for his class…
Oh oh is that guy cheating 
. Hey put down the iphone. Yes I’m talking to you, the one in the red shirt.
We teach a method called “Visual Integration” as well as the typical virtual work method for finding deflections of beams and frames. I did the math and it seems like a simpler system than integrating moment equations. (See video for lousy half-asleep explanation. tomorrow is our first big test!)
I was wondering if a) people teach this and b) does anybody have a reference for this method? (I have never seen a textbook with this method maybe it is sooo simple everybody knows it. Maybe its called something else? I can derive the method…..)
Let me know if you were taught this method, thanks!
Is this real? If the bridge is real, it is an amazing structure…..I am trying to figure out how you would build it.
Here in the frozen tundra, we are anxiously waiting for spring. (Or any temperature above freezing..) Tomorrow night I give my first exam. When I first started teaching I had a class of 20 and gave tests during class. Now with 55 students I have to give night exams from 8-10. I’m too old to stay up that late! Oh well on the bright side, it is supposed to be -4 tomorrow night…..
Aaron D. Feen on Flickr
I added Bridgehunter.com to my links page. (Yea for me I know and late to the party I also know.)
A great source of Historic bridge information and photos.
While your there play “name that truss“. I would lose…
bridgehunter.com
As Mark pointed out below, check out the bridgehunter.com’s guide to portal braces. One of the cool bridges shown below:
Bridgehunter.com