Right of weight,,,, in the most bad way

kamkar

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This could have become soooo bad.

 
Worst of all on the other side, it look as if a similar bus already crossed the bridge. o_O :sleep:
 
Are we sure the bus was over the weight limit? Apparently a 10 ton limit, but I don't have much idea of USA tons or bus weights...

Suspension bridges are supposed to sag under the weight of vehicles, my guess is that it was close to the limit but maybe not over...
 
One imperial ton is 2000lbs, which since 1kg is 2.2lbs, isn't too far off from one metric ton (1000kg/2200lbs). Even at 10 tons it's still close enough to be within the safety margin.

No idea what the weight limit for that bridge is, but I really doubt it was designed with that much deflection in mind.

And here are some specs on a nice bus like that: https://www.prevostcar.com/coach/h3-45

GVWR: 53000lbs, 24000kg
 
The bridge is designed to flex, but not that much obviously. I read that the DOT have inspected the bridge and it has been re-opened.
 
I'm sure the road-bed wasn't designed to flex that much, but the bridge structure could be OK with it. Because of the rocker pedestals, any load on the cable of a suspension bridge is spread over the entire cable and not at a single point. Design standards for these are 300% of maximum anticipated possible load, so with rated loads there's a safety factor of 4 or 5. But the decking and it's suspending structure is rated differently; it is designed to give way first to save the main structure from collapse. That's what the load limit usually settles on.

The Golden Gate bridge was designed and built without a properly certified Bridge Engineer. The load computations were done essentially by one man using nothing more complex than a manual adding machine; a 3+ year job in itself which could be done today with a few keystrokes in 10 minutes. Little was known about earthquake behavior back then, but because of quality construction by men who never gave less than their very best and that crucial 300% load allowance, it has held up better in storms and quakes that the newer bridges in the area whose designs are supposedly "advanced" and were done by certified Bridge Engineers.

Phil
 
I can't talk authoritatively about US design standards, despite studying engineering over there. This suspension bridge was designed back in the days of permissible / allowable stress design, when we applied a lumped factor of safety to everything (300%, or more if greater uncertainty).

Nowadays with Eurocodes here and ASD/LRFD over there, designs are done to limit state with a greater emphasis on detailed calculations and less on practical knowledge. The designs are supposedly more efficient, but they're sometimes less resilient to the biggest factor of uncertainty - people.
 
With most of the weak bridges here, you can't drive a bus across them due to physical restriction, you would struggle to even get a mini bus across this 3 T limit bridge:


Although you could probably get 30 cars on it and there is no warning against doing so...
 
Sure when its build by Isambard Kingdom Brunel,,,,,, talk about funny name,,,,,, still one that must be respected.
 
Sure when its build by Isambard Kingdom Brunel,,,,,, talk about funny name,,,,,, still one that must be respected.
Well it's a name that never gets forgotten!
But he didn't build that bridge, it is a David Rowell bridge, built in 1922.

Looks narrower on a proper camera:

3565426_bb7325c2.jpg


And it appears that I missed the 4 wheels and 4 mph speed limit sign! :

1584211_d599cc7e.jpg
 
No i dident thing so, just the first name that popped into my mind thinking of Old English builders.,,,, and yes i had to google the name as i was not quite sure on the spelling.
 
Build by a Dane for Australians.
Blog_Blogimage_SydneyOpera.jpg


Build by a Dane for Danes.
copenhagen_opera_house_image_1.jpg


Both Opera houses.
 
Hehe yes, if it was being build by Danes, they would still be building on it, and you will see budget explosions like never before.

The new Copenhagen opera house was only build on time and budget as it was a gift from Maersk shipping to the Danish people ( most of which would never go there )
And you dont f..k with Maersk, at least not if you are a Dane, but i think they are big enough to carry weight elsewhere too.
And besides Maersk probably been creative so much on his taxes that in truth its the Danes who paid for the sucker them self, and many times over.
 
4 mph, good luck getting anything on 4 wheels going that slow these days.
 
And besides Maersk probably been creative so much on his taxes that in truth its the Danes who paid for the sucker them self, and many times over.

Yes, seems to be true:
The Copenhagen Opera House is the national opera house of Denmark, and among the most modern opera houses in the world. It is also one of the most expensive opera houses ever built with construction costs well over US $500 million.
... the full cost of the project would be tax deductible, thus virtually forcing the government to buy the building;
... The bridges constructed to access the building were made from oak trees originally planted in the 19th century for use in replacing the national fleet that was lost with the bombardment of Copenhagen in September 1807.
... The acoustics were designed by Arup Acoustics.
https://en.wikipedia.org/wiki/Copenhagen_Opera_House

So an opera house that will only be used by a small number of people cost the small country of Denmark half a billion US$! The British (Arup) made a profit from it, and organised the planting of the wood for the bridges :D
 
4 mph, good luck getting anything on 4 wheels going that slow these days.
In the days when it was built, 4 mph was about top speed for a traction engine, although if you were only allowed 4 wheels then your engine couldn't pull any load over the bridge! You would have to get some horses for the load.
 
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