Del. I-495 emergency closure

[Alex4897]

so could dirt piles really be the cause?  or is it the media finding a scapegoat?  I just find it hard to believe piles of dirt can cause a bridge to shift.

Apparently it's a LOT of dirt.  I've heard well over 100 truckloads, and piled upwards of 2 stories high. When the tilting issue was first discovered, DelDOT immediately requested the removal of the dirt, so it's not something the media came up with a few days after the fact.

So I assume the bridge is tilting in the direction of the dirt piles?

[Alps]

*puts on engineering hat*
The foundation is designed based on soil conditions, including compressibility, pressure, weak spots, etc. Putting 20 feet of soil on top of one side of the foundation will definitely compress the soil - this exact strategy is used to compress clayey soils for new highway projects in a process called "surcharging", where the dirt stays on there for a year or two before the road is built so that the soil will have gotten most of its settlement over with. In this case, all of the added weight would push the soil down, thus pushing the foundation down, thus causing the column to tilt.
How to fix? That's tough. The soil will not uncompress itself. One solution is to try to pipe something under there - I was recently introduced to a foam product, but it wouldn't stand up to the loads of the foundation. Some sort of expanding and fast-setting grout type substance might work to boost the foundation back up where it started, as long as that substance won't compress over the next 50 years.
Another solution is to provide additional bracing from the side. With the right heavy equipment, the bridge can be lifted from the sunken columns onto newly designed columns, and straightened in situ. This is how the Central Artery was kept open in Boston during the Big Dig, and is the most likely scenario to be implemented in this case.
All of the news article commenters and anyone here who thinks a pile of dirt can't do this - you're wrong. It absolutely can. Put away your conspiracy theories.
*hat off*

[PurdueBill]

*puts on engineering hat*
...............
All of the news article commenters and anyone here who thinks a pile of dirt can't do this - you're wrong. It absolutely can. Put away your conspiracy theories.
*hat off*

I shudder reading comments on articles like these.  The "top commenter" crowd is often the absolute worst.  They achieve Top Commenter by quantity and not quality, obviously.

Most news articles do not need commenting enabled because there isn't all that much to really discuss.  So the comments take no time to degenerate into "Blame Obama, Blame Bush, blame whoever" drivel.  I'm surprised that sources like CNN haven't disabled comments for good.  Although they probably want to keep getting the page views from the commenters at least.

Arguing anything like explaining the engineering, surcharging, etc. to that crowd does no good.  All they do is turn on the one who knows what they're talking about and ridicules them, belittles, them, incorrectly "corrects" them, etc.  They aren't worth engaging in any discussion with.  I wonder what they are like in real life......

[ixnay]

Alps, FWIW "Puck" at http://www.delawareliberal.net/2014/06/05/delawares-i-495-closing-brings-attention-to-state-infrastructure/#comments suggested...

It's simple — we just need to dump an enormous pile of dirt on the other side of the bridge until the piers level out.

I assume he was being tongue in cheek.

ixnay

[Alps]

Alps, FWIW "Puck" at http://www.delawareliberal.net/2014/06/05/delawares-i-495-closing-brings-attention-to-state-infrastructure/#comments suggested...

It's simple — we just need to dump an enormous pile of dirt on the other side of the bridge until the piers level out.

I assume he was being tongue in cheek.

ixnay

It could work... but would then destabilize the piers on the other side. Plus now the whole bridge would have settled, requiring a whole new set of analyses.

*puts on engineering hat*
...............
All of the news article commenters and anyone here who thinks a pile of dirt can't do this - you're wrong. It absolutely can. Put away your conspiracy theories.
*hat off*

Arguing anything like explaining the engineering, surcharging, etc. to that crowd does no good.  All they do is turn on the one who knows what they're talking about and ridicules them, belittles, them, incorrectly "corrects" them, etc.  They aren't worth engaging in any discussion with.  I wonder what they are like in real life......

All of the top votes in the article I read - 6 up 0 down, etc. - were for the people who said "the media is covering this up! there's no way a pile of dirt can do this!" The hidden comment - 3 up 20 down, roughly - was the one person who actually said "I'm an engineer, and this is totally possible." I would have wept, but I mostly read article comments to laugh at how stupid people are. Fortunately, the DOT doesn't make decisions based on article commenters.

[amroad17]

Are the piles of dirt in the I-495 photo the ones in question?

[cpzilliacus]

*puts on engineering hat*

Thank you.

The foundation is designed based on soil conditions, including compressibility, pressure, weak spots, etc. Putting 20 feet of soil on top of one side of the foundation will definitely compress the soil - this exact strategy is used to compress clayey soils for new highway projects in a process called "surcharging", where the dirt stays on there for a year or two before the road is built so that the soil will have gotten most of its settlement over with. In this case, all of the added weight would push the soil down, thus pushing the foundation down, thus causing the column to tilt.
How to fix? That's tough. The soil will not uncompress itself. One solution is to try to pipe something under there - I was recently introduced to a foam product, but it wouldn't stand up to the loads of the foundation. Some sort of expanding and fast-setting grout type substance might work to boost the foundation back up where it started, as long as that substance won't compress over the next 50 years.

Do you think that would "straighten" the piers - or are you suggesting that they be shored-up and left leaning (slightly)?

Another solution is to provide additional bracing from the side. With the right heavy equipment, the bridge can be lifted from the sunken columns onto newly designed columns, and straightened in situ. This is how the Central Artery was kept open in Boston during the Big Dig, and is the most likely scenario to be implemented in this case.
All of the news article commenters and anyone here who thinks a pile of dirt can't do this - you're wrong. It absolutely can.

I heard it explained elsewhere that the soil under the bridge is something like a big mattress, and when something heavy (as in the dirt) is put on the edge of that mattress, then the entire mattress will tend to deform to some extent, not just the place where the "new" weight was added.

Would it be possible to remediate the problem by holding the bridge up with something temporary (as in your Central Artery example above), and then demolishing and rebuilding the "leaning" piers?

Put away your conspiracy theories.*hat off*

Agreed!

[Alps]

How to fix? That's tough. The soil will not uncompress itself. One solution is to try to pipe something under there - I was recently introduced to a foam product, but it wouldn't stand up to the loads of the foundation. Some sort of expanding and fast-setting grout type substance might work to boost the foundation back up where it started, as long as that substance won't compress over the next 50 years.

Do you think that would "straighten" the piers - or are you suggesting that they be shored-up and left leaning (slightly)?

The idea would be to raise the foundations back to where they started, which should correct the lean. The columns would have to be temporarily shored during this time. I don't think it's feasible, though.

Another solution is to provide additional bracing from the side. With the right heavy equipment, the bridge can be lifted from the sunken columns onto newly designed columns, and straightened in situ. This is how the Central Artery was kept open in Boston during the Big Dig, and is the most likely scenario to be implemented in this case.
All of the news article commenters and anyone here who thinks a pile of dirt can't do this - you're wrong. It absolutely can.

I heard it explained elsewhere that the soil under the bridge is something like a big mattress, and when something heavy (as in the dirt) is put on the edge of that mattress, then the entire mattress will tend to deform to some extent, not just the place where the "new" weight was added.

Would it be possible to remediate the problem by holding the bridge up with something temporary (as in your Central Artery example above), and then demolishing and rebuilding the "leaning" piers?

That may end up being the answer. I don't know, sitting here, whether it's more expensive to build a Central Artery type system as a 20-30 year stopgap before the whole bridge is replaced, or to build a temporary scaffold and repour the columns. I think the former is the better value, but that's just what I think at 24:08.

[Pete from Boston]

What is the projected timeline for an alternatives analysis?  Presumably, it could go on infinitely, but presumably, the timeline for doing it is compressed due to the cost of the closed road. 

[Alps]

What is the projected timeline for an alternatives analysis?  Presumably, it could go on infinitely, but presumably, the timeline for doing it is compressed due to the cost of the closed road. 

There will probably be an abbreviated constructability review in coordination with the geotechnical assessment of soil conditions. They're not going to go crazy trying to find the cheapest or quickest option. Whatever they can pull together in a week or two, they're going to throw straight into the final design phase. I-43 Fox River was closed a little over 3 months, I think we're looking at a similar timeframe here.

[ixnay]

Americans in 50 states and DC will be stuck with part of the bill...

http://wdel.com/story.php?id=59961

ixnay

[SteveG1988]

Americans in 50 states and DC will be stuck with part of the bill...

http://wdel.com/story.php?id=59961

ixnay

Yes. that is how interstate highways are funded.

[KEVIN_224]

http://www.delawareonline.com/story/news/traffic/2014/06/05/markell-weeks-months-reopens-delaware/10032061/

Some of the same press conference from delawareonline.com ^^^

[cpzilliacus]

That may end up being the answer. I don't know, sitting here, whether it's more expensive to build a Central Artery type system as a 20-30 year stopgap before the whole bridge is replaced, or to build a temporary scaffold and repour the columns. I think the former is the better value, but that's just what I think at 24:08.

Understood.  Appreciate your informed commentary. 

Seems to me that they could build something "temporary" to hold the bridge up, and then demolish and replace the columns.  Now could the bridge be open to traffic with sometime temporary in place?  I have absolutely no idea, but I hope the bridge engineers give that some thought, since even if the replacement columns get poured in a matter of days, they have to cure for at least a month, right?

Reminds me of this:

D.C. DPW (before there was a DDOT) discovered a serious problem with the structural supports (might have been the piers) that held up the bridge that carries D.C. 295 over Nannie Helen Burroughs Avenue, N.E. about 10 or 12 years ago. 

A closure was not an option, so falsework was hastily designed and constructed out of steel I-beams and put up by a bridge construction crew that was diverted from an unrelated DDOT bridge project on the other side of town. That falsework rested on (IIRC) railroad ties which in turn rested on pavement. 

It remained that way for between 5 and 10 years, but a few years ago, the bridge was totally reconstructed and the falsework was removed.

[cpzilliacus]

Americans in 50 states and DC will be stuck with part of the bill...

http://wdel.com/story.php?id=59961

Most of the cost of construction of this Interstate highway was funded by federal tax dollars.

What is your concern?

[jeffandnicole]

http://www.delawareonline.com/story/news/traffic/2014/06/05/markell-weeks-months-reopens-delaware/10032061/

Some of the same press conference from delawareonline.com ^^^

Generally I don't like newspapers airing videos, because you have a newspaper journalist acting as a television reporter.  They can be painful to listen to.  In this case, they simply put together what DelDOT engineers and the Governor had to say, and it was very insightful.

I wonder if there's any sort of pictures or video showing the bridge over a period of time to try to determine when the bridge really started tilting.  Even something like State Police vehicle dash video stored on a hard drive, if the camera is always on, could reveal when the bridge started shifting.

Federal Funding: People don't understand how funding works, so those stories can be easily written to mislead the public (no doubt they probably are).  Even a simple traffic light or sign could be paid for by people across all 50 states, if the Feds provided the state with funding for various programs, then the state passed that money down to the local counties or municipalities. 

It's becoming fairly clear what the issue is, and I feel bad for the contractor as well because he was probably directed to dump the dirt where he did, and no one knew or thought otherwise.  It seems to be clear it's not a case of illegal dumping, as they knew right away who the contractor was.

Looking at the Facebook comments from friends who live in Delaware - especially those that work in the Philly area - they've been dealing with some serious delays as they try to figure out alternate routes, generally increasing their commute time by double or close to triple. 

Regarding the statement that transportation costs have increased for truckers as they are using the NJ Turnpike as a bypass: A typical 5 axle truck would pay anywhere from $43 - $50 to travel the length of the Turnpike, depending on the time and method of payment.  Plus the cost of the Delaware Memorial Bridge.  So roundtrip, it could add about $100 or so to the transportation costs.  Depending on the origin/destination, more than likely it's a bit less than that as the trucks would've used the northern portion of the NJ Turnpike anyway, they could use 295, or would've had a destination closer than NYC that didn't involve the entire Turnpike.

[D-Dey65]

I shudder reading comments on articles like these.  The "top commenter" crowd is often the absolute worst.  They achieve Top Commenter by quantity and not quality, obviously.

Most news articles do not need commenting enabled because there isn't all that much to really discuss.  So the comments take no time to degenerate into "Blame Obama, Blame Bush, blame whoever" drivel.

A couple of prime examples of that:

Anthony Malvoso ·  Top Commenter · Lamar University

And the GOP still refuses to spend any money on infrastructure repairs.
Democrats,
If you vote we win.
It's that simple !

Gary Fowler · CDL-A Driver at Mother-trucker
Is that where Obama's shovel ready jobs money went?

What difference does it make if DelDOT doesn't consider using that money to strengthen that bridge?

DerpDerpConservativesDerp > JazzBo

You know what other money could go to fixing bridges? The money we use to bomb other countries, or the money we use to fund a military that spends twice as much as any other country in the world, or the money that goes to fight the bogus war on drugs, or the money we could make from raising corporate taxes back to Ronald Reagan numbers, or literally a thousand other ways that people fight and then whine about spits in the bucket like immigration or welfare.

FYI, Derp, the people we're bombing are the ones who would blow that bridge to smithereens during rush hour.

Arguing anything like explaining the engineering, surcharging, etc. to that crowd does no good.  All they do is turn on the one who knows what they're talking about and ridicules them, belittles, them, incorrectly "corrects" them, etc.  They aren't worth engaging in any discussion with.  I wonder what they are like in real life......

Probably the same, and if not, they could be hiding how they feel, and only say what they do on the net. I haven't seen anyone try to correct these fools, but I have a feeling that if you did, they'd accuse you of being a tool for the government of some idiotic ready-made accusation like that.

[jeffandnicole]

http://www.delawareonline.com/story/news/traffic/2014/06/05/markell-weeks-months-reopens-delaware/10032061/

Engineers investigating the leaning bridge that was shut down along I-495 this week discovered that steel piles in the bridge's foundation are deformed and displaced sideways, creating cracks across the width of at least two concrete footings, state officials said Thursday.

[ixnay]

Americans in 50 states and DC will be stuck with part of the bill...

http://wdel.com/story.php?id=59961

ixnay

Yes. that is how interstate highways are funded.

Indeed.

ixnay

[ixnay]

Americans in 50 states and DC will be stuck with part of the bill...

http://wdel.com/story.php?id=59961

Most of the cost of construction of this Interstate highway was funded by federal tax dollars.

What is your concern?

Curiosity, since this is for repair and not the original construction.

This quote from jeffandnicole...

Federal Funding: People don't understand how funding works, so those stories can be easily written to mislead the public (no doubt they probably are).  Even a simple traffic light or sign could be paid for by people across all 50 states, if the Feds provided the state with funding for various programs, then the state passed that money down to the local counties or municipalities. 

... seems to answer my question best.

ixnay

[NJRoadfan]

Americans in 50 states and DC will be stuck with part of the bill...

http://wdel.com/story.php?id=59961

ixnay

Its Delaware, they'll find a way to get everyone else to pay for it.

[Alex]

Americans in 50 states and DC will be stuck with part of the bill...

http://wdel.com/story.php?id=59961

ixnay

Its Delaware, they'll find a way to get everyone else to pay for it.

It could be a good time to make the Christina River crossing a toll bridge! 

[Alex4897]

Americans in 50 states and DC will be stuck with part of the bill...

http://wdel.com/story.php?id=59961

ixnay

Its Delaware, they'll find a way to get everyone else to pay for it.

It could be a good time to make the Christina River crossing a toll bridge! 

Why not go big and build a toll tunnel?   

[cpzilliacus]

It could be a good time to make the Christina River crossing a toll bridge! 

That would (effectively) turn I-495 into an express toll lane-type of bypass of Wilmington, though I suppose that many trucks would have to pay anyway, since there are low-overhead clearance bridges on the part of I-95 that runs parallel to I-495 in New Castle County.

[jeffandnicole]

It could be a good time to make the Christina River crossing a toll bridge! 

That would (effectively) turn I-495 into an express toll lane-type of bypass of Wilmington, though I suppose that many trucks would have to pay anyway, since there are low-overhead clearance bridges on the part of I-95 that runs parallel to I-495 in New Castle County.

The lowest clearance on 95 is 14'0". Trucks are limited to 13'6", so they are fully able to use I-95. It would be the extremely rare over height truck that would be prohibited, and they have so many other limitations in the area (traffic lights, power lines, etc) that they are rarely on the road without a major escort.