Instant Bridges

czsz

czsz

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http://www.nytimes.com/2012/04/18/u...iques-transform-infrastructure-repair.html?hp

BOSTON — The River Street Bridge here is normally unremarkable, the kind of structure people drive over every day without a thought. When it fell into disrepair, state officials knew that replacing it would normally involve two years of detours and frustration for local drivers.

Instead, they did it over a weekend.

By using “accelerated bridge construction” techniques, a collection of technologies and methods that can shave months if not years off the process of building and replacing critical infrastructure, Massachusetts is at the forefront of a national effort that is aimed at putting drivers first.

“This will be the new normal,” said Victor M. Mendez, the head of the Federal Highway Administration.
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Waiting for someone here to tell me the downside of this, and/or how unions are insidiously benefiting at the public's expense in some way despite this being as good as it sounds...
 
czsz said:
http://www.nytimes.com/2012/04/18/u...iques-transform-infrastructure-repair.html?hp



Waiting for someone here to tell me the downside of this, and/or how unions are insidiously benefiting at the public's expense in some way despite this being as good as it sounds...
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Nope, it's pretty popular. They did it in Chicago a couple of times when I lived there. It does require the ability to either build the bridge next door or drive it in (wide load), which limits its potential in Boston, I'd expect.
 
I've seen it done around the burbs twice and each time I thought it worked great. The minor inconvenience of a weekend bridge closing pales in comparison to the years of slogging through traditional replacement/renovation.
 
This is really a great advance. I know the bridge at RT 53 that crosses rt 3 in hanover has taken a decade to get moving (largely a funding issue). This is a great way to modernize our infrastructure efficiently, and maybe save some marginal savings. plus, in a case like this, i think success begets success. If people can replace a bridge in their town knowing it won't be a 2-3 year nightmare, they will be more willing to pay for it. And this country, and especially this area needs infrastructure upgrades. I am sure if you did a study on this method vs. previous ones, you would find enormous economic benefits from doing it this way. Everything from gas and traffic savings to potential lost revenue at nearby businesses.

In risk of getting off track which has been a problem, sometimes when bored at work I will read a random Herald article and click the comments and see how long it takes to get to see the word "Obummer" "DeVALUE" or "Libtard". No matter what the article usually you don't have to go beyond comment 5. This article would be a great case study.
 
Equilibria said:
Nope, it's pretty popular. They did it in Chicago a couple of times when I lived there. It does require the ability to either build the bridge next door or drive it in (wide load), which limits its potential in Boston, I'd expect.
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It's a bridge.

Boat it in!

(Can it be done this way?)
 
I read this post and first thought you were talking about the River Street bridge over the Charles River. That would probably not be easy to rebuild using this method.
 
This technique is not new nor is it unique to only bridge construction.

Many buildings are constructed in matter of days using this technique including these two, one from Melbourne, and the other in Hunan.

lilhero.jpg


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The one from Hunan was built in 15 days.
 
I-93 "Fast 14" won all kinds of civil engineering awards it was such a smashing success. They're good bridges, too. Fast does not equal cheap quality. I drove under the Route 16 Medford bridge about a week ago in a traffic jam and got a decent look underneath. Very high-quality craftsmanship for something assembled in 72 hours. Ditto all the Fairmount Line overpasses they replaced this summer in similar around-the-clock weekend shifts. Those even have some neat aesthetic curves on them much improved from the fugly old 19th century girder bridges.

This is a national model to follow. For one, there's little wiggle room for mission creep on a project or chance to blow out a budget unless something goes wrong on the roadside pre-assembly (which also has to happen relatively quick to avoid complaints with the neighbors). State can make good hay on its backlog of bridge repairs doing them in bulk this way, and save way more money than frivolous things like that 128 overpass in Waltham that took like 3 years to build with all kinds of pointless decorative dodads that nobody cares about. This is the way to do it when you're climbing out of an infrastructure maintenance hole.
 
Of course there's still the whole question of whether you would want a building like the one built in Hunan....Changsha?
 
I'm under the impression that the Berklee midrise will be pre-fabbed and dry-fitted offsite before being hauled in and craned up for final welds. Suppose it makes sense to do this type of construction when a site is constrained by size or traffic and stuff.
 
TMcLaughlin said:
http://www.youtube.com/watch?v=Jx7LyKnOl80

MassDOT is getting experienced in this. Hopefully this is the new normal.
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It totally is. MassHighway and the T have basically scheduled a few of these per year until the end of time. And if Congress ever ungridlocks enough to fund an infrastructure bank for this purpose you'll see the pace of this pick up wildly to the point where they may be doing a "Fast 14" every year.

Totally worth it. So much less community resistance to the 'tear the Band-Aid off fast' approach, and even moreso the narrow margin of error for anything to go over-budget. Can even see in the NY Times video about the River St. bridge that they had an unanticipated mis-alignment issue from some wrong engineering calculation that they fixed in 2 hours flat where it would normally set back a project weeks. No room for contractor sloth in these deals because of the penalties for not being ready for Monday morning traffic. That makes for better preparation, fewer cut corners from laziness...and less corruption. Big business and big politics always takes the lazy way out. It a big fucking deal to cut out that whole margin for laziness and make vengeance swift and brutal for gakking it. That is fully evident in the quality of worksmanship on these replacements done in the last 12 months.

The price is going to drop even further in the future because more contractors are going to train themselves on these methods to satisfy the near-limitless demand. This truly is revolutionary and probably the biggest single piece of good news to be had about working through the daunting backlog of deficient bridge replacements in every state in the country.

Only ones you can't do this on are bridges over water, historic/signature spans, ones with such tight clearances there's no staging space, and other quirks. Which are a decided minority of the deficient bridges to work through when you consider that in the postwar era states bulldozed acres of buffer space without second thought around any new road structure. Those 1940's-60's highway bridges are the biggest chunk of the backlog. There aren't too too many of these real oldies left like River St. that are pushing their luck to a century. Those leftovers of 19th century-era construction are more prevalent in urban cores and on creaky old rail lines, and they're disappearing fast as new-wave urban renewal sweeps big cities past the immediate downtown areas that got all the attention in the 90's-00's and into the next-closest surrounding neighborhoods. And rail lines make a big general push to fix lots of little things up as they work through the PTC mandate and getting up to the new freight weight standards where all the shipping revenue is these days. But those first-wave Interstate highway bridges are where these replacements are going to hit a dizzying pace once this becomes the norm and the supply of qualified contractors scales to meet demand.
 
I was rather impressed with the Fast 14 in 93. Watching the videos and seeing the work while driving by was great. It has to be one of the more successful infrastructure projects this area has ever done.

Makes you scratch your head that they can replace an entire bring on a busy expressway in 2 weekends, but to build an elevator at Park Street takes 2 plus years.
 
I bet if they locked them in for a week and told them to get it done they could do it. Unfortunately, park street and the T are a little harder to work around for people. I bet if they gave people enough notice, shut down for a week, and ran trains through- as both DTX and Boylston/Gov't Center are close enough to not really burden anyone. Actually it could really work on second thought.
 
F-Line to Dudley said:
I-93 "Fast 14" won all kinds of civil engineering awards it was such a smashing success. They're good bridges, too. Fast does not equal cheap quality. I drove under the Route 16 Medford bridge about a week ago in a traffic jam and got a decent look underneath. Very high-quality craftsmanship for something assembled in 72 hours. Ditto all the Fairmount Line overpasses they replaced this summer in similar around-the-clock weekend shifts. Those even have some neat aesthetic curves on them much improved from the fugly old 19th century girder bridges.

This is a national model to follow. For one, there's little wiggle room for mission creep on a project or chance to blow out a budget unless something goes wrong on the roadside pre-assembly (which also has to happen relatively quick to avoid complaints with the neighbors). State can make good hay on its backlog of bridge repairs doing them in bulk this way, and save way more money than frivolous things like that 128 overpass in Waltham that took like 3 years to build with all kinds of pointless decorative dodads that nobody cares about. This is the way to do it when you're climbing out of an infrastructure maintenance hole.
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Fast 14 was a great money/time saver. But it's not a cure-all. You can't build a Fast 14:
  • Over water (need to be able to demo bridge deck onto area below bridge)
  • Over another active road (again, need to close road below to demo bridge deck)
  • In areas where the bridges can't be accessed by extra large trailers
  • In areas that don't have the mobilization space for multiple 200 ton cranes
  • On a bridge more than a 15 minute drive from a DOT certified concrete factory (because you need to use an accelerant in the concrete if you expect to open the bridge Monday morning)
  • On bridges that have anything wrong with them beyond a structurally deficient deck (because you're not fixing the abutments or widening the bridge - your just replacing the deck)
So, for example, the Winter Street bridge in Waltham that F-Line referenced would never be a candidate since there's an active highway beneath it and the bridge was significantly widened and realigned.

The other issue with Fast 14 is the use of high early strength concrete. For a normal bridge DOT might want the concrete to get to 3000 PSI within 7 days and 4000 PSI within 28 days. On the Fast 14, they were shooting for (I believe) 3000 PSI within 6 hours and 4000 PSI within 24 hours. I spoke to a DOT engineer who said they began to see cracking on the HES concrete within the first week after it was set. Not structurally deficient cracks that are going to make the bridge unsafe, but little hairline cracks that will let water in and (they're concerned) dramatically reduce the life of the bridges. Of course, they don't know yet because this has never been done on such a large scale in the US.

All in all I still think it's a plus. Even if the HES reduces the life of the bridge by 20 years I still suspect this method saves money (and headaches).
 
Two of the Fast 14 bridge replacements were over the Mystic River, and the rest were all over active roads (that were closed for a weekend at a time).
 
See Kieran Timberlake's Refabricating Architecture.
 
Ron Newman said:
Two of the Fast 14 bridge replacements were over the Mystic River, and the rest were all over active roads (that were closed for a weekend at a time).
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They put barges down in the Mystic and covered them with steel plates (basically barge, to barge to barge to shore - a constant line of steel plates). That gets very expensive, very fast on a large river (Mystic crossing is only about 80' over water).

And the other active roads needed to be closed - hence they weren't active. My point was that it's not as easy to justify this type of project on a bridge over a highway (e.g., the Winter Street bridge in Waltham). I agree, it works for a highway bridge over a smaller surface road that can be easily detoured.
 
AmericanFolkLegend said:
They put barges down in the Mystic and covered them with steel plates (basically barge, to barge to barge to shore - a constant line of steel plates). That gets very expensive, very fast on a large river (Mystic crossing is only about 80' over water).

And the other active roads needed to be closed - hence they weren't active. My point was that it's not as easy to justify this type of project on a bridge over a highway (e.g., the Winter Street bridge in Waltham). I agree, it works for a highway bridge over a smaller surface road that can be easily detoured.
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Relevant point is that it must strike fear into the unions and their sycophant contractors

Even if someone comes-up with a fix for the problems identified by F-Line that takes a month or even three and the process ends-up totally different than today's "Fast" bridge replacement approach -- Pandora's Box has been open and creative chaos has spewed-forth. In the future whenever reconstruction or perhaps even new construction is on the table -- the "old way" won't ever stand-up automatically without serious scrutiny.

Indeed if anything accidentally good came from the Stimulus -- this might be it.
 
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