Modern Marvels - Bridge Building

[tallyho8]

I am amazed by the engineering they are using to widen the 75 year old Huey P Long Bridge over the Mississippi River outside New Orleans. This is the longest train-auto cantilever bridge in the world but it was built with 2 very narrow car lanes on each side with no shoulders.

They are widening it to 3 wide lanes on each side with shoulders. This has been in the planning stage for years and many of us were worried that this bridge would be closed for months on end while work was being done. The engineers have figured out how to widen it without closing it off for more than a couple of days.

There are 3 giant spans that are being pre-assembled and barged in and they will be placed under the bridge and lifted up around it. These spans are the full 6 lanes wide with the centers cut out where they will wrap around the train bridge and the existing roadways.

The smallest span is scheduled to be lifted next month and it is 528 feet long and weighs 5,300,000 pounds. In the photos you can see the small span on barges in the river and you can see where the spans will be connected to the part of the bridge that has been built in place.

I believe the local TV stations will have cameras on it the whole time in case something goes wrong.

If you want more info on the project you can visit their web site. Louisiana TIMED Program Huey P. Long Bridge Widening

 

[Dmace]

That's awesome! I love watching those Modern Marvel shows, it would be nice to see one on this bridge. It's amazing what you can make float with enough displacement.

 

[IH3444]

I'm so addicted to watching those shows such as modern marvels, history channel, discovery channel, science channel, etc. That I also buy the DVDs as cheap as I can find them if I miss a program in a series I really like. I need help........I can't quit on just my own will power!

Gotta go, it back on!

 

[Tdog]

Did Tally mention that the original Huey P. had REALLY narrow lanes. It was built for traffic in the 1930's, smaller & slower than now. I can't believe that my wife used to cross that bridge once a week pulling a horse trailer, taking our daughter to riding lessons. Man she was motivated.

Jack

 

[czechsonofagun]

Looks great. For me job well planned and done with good engineering to show is more of an achievement than football or any sport.

 

[tallyho8]

I will try to get some photos of it when they are lifting the giant spans and post them.

It still amazes me that while they are busy closing bridges across the country because they are 50 years old and collapsing, they are tripling the size of this 75 year old bridge. And doing it without any major shutdowns in the traffic flow!

My uncle left me a portfolio he made while they were originally building the bridge with lots of photos and newspaper articles. I may combine them with the new photos and stories and make a little story for the local paper.

Before they built this bridge, the Union Pacific railroad crossed the river on barges with tracks that they set each time they crossed it. They built this bridge to save them time and Governor Long talked them into letting them connect auto lanes to it after they had already made plans and construction was started.

What I could not believe was that this only saved the railroad 45 minutes with each crossing. They must have been able to set up barges awful quick in the old days.

 

[czechsonofagun]

Human work and ingenuity - always the most fascinating story. Looking forward to more pictures

 

[2manyrocks]

Most of us would cross the bridge without the first clue of the engineering that went into it. I think we'd have more kids interested in engineering if the schools would put aside some of their regular teaching fare for someone to explain a project like this to them.

 

[mmurphy]

Just think about how deep the pilings would have to go for all that weight. Might be shaking a china man out of bed!!!!:laughing:

 

[tallyho8]

Just think about how deep the pilings would have to go for all that weight. Might be shaking a china man out of bed!!!!:laughing:

Actually, I don't believe that their are any pilings under the piers in the water. The piers are just sitting on a layer of sand about 200' below the surface and just depend on their enormous size and weight to hold them in place.