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Section of I-95 collapses after fire burns under overpass...
15

Section of I-95 collapses after fire burns under overpass...

Section of I-95 collapses after fire burns under overpass...

(OP)
Portion of Interstate 95 collapses in Philadelphia after tanker fire burns under overpass

A tractor trailer fire started under an I-95 overpass and spread to the lanes above.


https://6abc.com/interstate-95-collapse-i-95-fire-...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

Looks like a fairly simple structure, with steel I-beams spanning between the diagonal abutments, lightweight bracing between the beams, and a poured concrete deck on top. Google Street View has pretty good imagery of the underside of the bridge:

https://goo.gl/maps/3JSJ6Gb9dQhUGKUw7

RE: Section of I-95 collapses after fire burns under overpass...

From the fire dispatch audio
0622....initial alarm
0627....on scene, requested box alarm
0628....requested hazmat task force
0629....request complete shut down of I-95
0647....notify DOT that NB I-95 has collapsed

RE: Section of I-95 collapses after fire burns under overpass...

Looks like the steel softened sagged, and eventually the weight of the deck, which can not support itself with out the strength of the steel substructure, pulled one end off of the abutment. It took a very hot fire to do this in 20 minutes.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
Yes, this image shows the damage and indications as to the intensity of the fire:



John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

We had a tanker fire under an overpass a few years back in the San Francisco bay area. It caused some spalling of the concrete but there was no structural damage.

https://www.mercurynews.com/2008/10/22/southbound-...

This one was kind of funny. A motorcycle wiped out merging onto the freeway and wedged itself under a tanker truck causing it to catch on fire. Nobody was hurt. I've wiped out on a motorcycle merging onto the freeway... Luckily nobody was injured there, either.

https://www.mercurynews.com/2020/10/24/richmond-sh...

RE: Section of I-95 collapses after fire burns under overpass...

video: Pennsylvania Gov. Shapiro gives news briefing on I-95 overpass collapse
I have seen the results of 2 fuel tanker fires, both were fortunately on top of a bridge with the result tug reports, spalled concrete. Concrete is a really fire resistant material. Compost construction bridges do not as far as I am aware protect the steel structure with fire proofing as is commonly used in buildings to protect steel members. So direct exposure to fire will heat the steel faster and hotter.

This enlargement from a picture here https://www.mcall.com/2023/06/11/i-95-bridge-colla... clearly shows the bridge steel bent in a manner that can only happen when the steel is heated above forming temperature.


Underside of bridge showing steel. https://www.google.com/maps/@40.0244766,-75.030809...

RE: Section of I-95 collapses after fire burns under overpass...

I believe that this was sabotage ... The 9000 gallon Tanker Truck was way, way too accurately positioned !!!

Anybody agree with me ???

MJCronin
Sr. Process Engineer

RE: Section of I-95 collapses after fire burns under overpass...

The videos are pretty crazy; the overpass was sagging at least 6 inches in a couple of the videos where people were driving on the overpass while the fire was going full blast. No doubt that the steel beams were on the verge of collapse

TTFN (ta ta for now)
I can do absolutely anything. I'm an expert! https://www.youtube.com/watch?v=BKorP55Aqvg
FAQ731-376: Eng-Tips.com Forum Policies forum1529: Translation Assistance for Engineers Entire Forum list http://www.eng-tips.com/forumlist.cfm

RE: Section of I-95 collapses after fire burns under overpass...

Quote (MJCronin)

I believe that this was sabotage Y/N?
As an engineer, no I do not think so and not important to the discussion at this time. If i was an investigator yes, needs to be investigated.

RE: Section of I-95 collapses after fire burns under overpass...

The road going under the bridge makes an abrupt curve to the left just before going under the bridge. My guess is that the gasoline tanker was going too fast for the curve and overturned. But that is just my guess.

RE: Section of I-95 collapses after fire burns under overpass...

2
Brush Fire on I-95 Twitter laughtearslaughtearslaughtearslaughtearslaughtearsspin2autospin2laughtearslaughtearslaughtearslaughtearslaughtears...... !!!!!!!hairpull2!!!!!!!

Be carefull Twitter

If you didn't think folks were vulnerable, these two videos might prompt a rethink.

RE: Section of I-95 collapses after fire burns under overpass...

Holy shit, they almost ended up in the fireball. Crazy video. Thank god concrete is so great for fireproofing. So lucky this was early Sunday morning, imagine if this was rush hour, nuts.

What kind of temperatures would it have needed to get under there to collapse these beams?

RE: Section of I-95 collapses after fire burns under overpass...

Steel starts to weaken at about 600F, loses half strength by 1100F, and it is all downhill from there.

RE: Section of I-95 collapses after fire burns under overpass...

Yup... both loss of Es as well as yield...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Section of I-95 collapses after fire burns under overpass...

wow - those people really wanted to cross that bridge...

--- Best regards, Morten Andersen

RE: Section of I-95 collapses after fire burns under overpass...

I would have thought that a risk analysis would have come up with the possibility of a fire in that quite long underpass and designed accordingly. Say using concrete beans? Or adding some level of fire resistance?

The effect of fires in an enclosed space are well known, especially in tunnels.

Not sure who made the decision to close the road but this could have ended very badly.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Section of I-95 collapses after fire burns under overpass...

This search turns up some interesting items https://duckduckgo.com/?t=lm&q=protection+of+b...
A quick skim seems to indicate that designing highway bridges to account for fire risk is a new thing.

The Society of Fire Protection Engineers: Bridge Fires: Fiction or Reality? - Well we have another example.

Quote (https://www.sfpe.org/publications/periodicals/sfpe...)

Introduction

Fire protection engineering has mainly focused on two areas: buildings and tunnels, which have their own standards and about which a large number of studies have been published. What about other types of infrastructure, such as bridges? Are they outside the scope of fire studies? One could think that the probability of a bridge being affected by a fire does not merit special study, but is this really so?

RE: Section of I-95 collapses after fire burns under overpass...

So when does a long underpass turn into a tunnel?

Might need to be a fire dept SOP to stop traffic when there is a fire under a bridge section?

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Section of I-95 collapses after fire burns under overpass...

4
I'll posit the theory that we can't and shouldn't design bridges for every eventuality... And I think this sort of scenario is likely better addressed on the trucking side than the bridge side.

RE: Section of I-95 collapses after fire burns under overpass...

Maybe so, but when a specific bridge has this on the off ramp ( about 100m from the underpass)then it suddenly ramps up the probability of a crash by a facto of 10 or 100 or maybe 1000 compared to any other bridge.

No one is going to do 25mph coming off a freeway when they can't see the road in front of them bending left.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Section of I-95 collapses after fire burns under overpass...

The structure was new in 2016. Perhaps an overshoot runout is practical in these situations.


Google Maps

RE: Section of I-95 collapses after fire burns under overpass...

The structure might be 2016, but the underpass was there in 1992.

They missed an opportunity there but maybe that's what happens with widening schemes as opposed to new ones

The underpass nearly doubled in length and is now about 50-60m long.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Section of I-95 collapses after fire burns under overpass...

Is there any chance the probably damaged southbound side could be cribbed up to support traffic while the northbound lane is repaired? That would really ease the traffic on whatever detour they set up. It might help more if some of the northbound traffic could be crossed over to the southbound side to temporarily share the cribbed up bridge, and then have southbound traffic crossed over to share the new northbound bridge while the southbound side is repaired. It would be inconvenient, but probably not as bad as any surface street detour.

RE: Section of I-95 collapses after fire burns under overpass...

They should be able to install a whole bunch of supports on the remaining carriageway and close the off ramp??

Or is that what "cribbed up" means?

But the concrete may have been severely damaged as well.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Section of I-95 collapses after fire burns under overpass...

I was thinking something similar R46. But would the shoring even work if the steel itself is compromised?

Are there any tests or what's the method used to evaluate steel that has been heated/ fire damaged badly?

RE: Section of I-95 collapses after fire burns under overpass...

@LittleInch,
The fire department incident commander requested that the state police shut down both directions of the I-75 two minutes after they arrived on scene. No idea how long it took before the road was actually shut down.

RE: Section of I-95 collapses after fire burns under overpass...

Good call by the FD.

Missed the timeline earlier.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

RE: Section of I-95 collapses after fire burns under overpass...

Once steel cools it regains it's annealed state properties. After cribbing there is still the deformed deck to deal with.

Quote (Attached is a FWHA memorandum )

Several questions have centered on the definition of a tunnel and which types of structures are
subject to the NTIS. This memo provides further guidance on different structure types that are or
are not subject to the NTIS and can be used to guide efforts to inventory all highway tunnels by
December 11, 2015 as required by the regulation.

It's a bit long winded, but supports the idea that a bridge can become tunnel like for the purposes of the inspection program.

RE: Section of I-95 collapses after fire burns under overpass...

There are a lot of talented bridge engineers out there. I’m interested to see what they come up with given the circumstances and political pressure to get these lanes reopened.

RE: Section of I-95 collapses after fire burns under overpass...

By "cribbed up" I meant whatever temporary support is needed to make it safe to use.

Moot point, I guess. According to inquirer.com news update posted shortly after 5pm, the southbound bridge will need to be demolished.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
At least one body has been found under the collapsed overpass:

I-95 collapse rescue teams find human remains in wreckage of tanker fire disaster in Philadelphia

https://www.cbsnews.com/news/i-95-collapse-human-r...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

As mentioned earlier in the thread, this has happened in the Bay Area famously. Here's a good short documentary of the fire and subsequent incredibly rapid reconstruction https://www.youtube.com/watch?v=-TKjwblp1XI

In the Oakland case, the fault was on the driver. The driver and company lost their DOT Hazmat endorsements. I suspect the same will happen here. Both occurred on curves where the driver (probably) was not driving appropriately for the conditions. I tend to agree with Lomarandil that designing for fires may not be the best solution. Truckers should be able to drive along a curve without crashing, especially when there is signage stating the speed and roll over potential.

Edit: coincidentally this Frontline Documentary has just aired America’s Dangerous Trucks

RE: Section of I-95 collapses after fire burns under overpass...

From the Pennsylvania DOT update https://www.penndot.pa.gov/RegionalOffices/distric... :
"In consultation with federal engineers from the Federal Highway Administration, PennDOT has hired a contractor – Philadelphia-based contractor Buckley & Company – to backfill the gap in the roadway so that it can be paved over and reopened safely and as quickly as possible. Once complete, cars and trucks can return to this portion of I-95 as crews work to rebuild a permanent bridge while keeping six lanes of traffic flowing at all times."

That's welcome news for everyone who uses that route.

A live feed is being set up so everyone can watch the work 24/7. That's going to be interesting.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
That's a rather creative, albeit temporary, solution to restoring the flow of traffic.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

Governor Shapiro is hellbent on getting the highway reopened, and keeping six lanes open as the work progresses. https://www.youtube.com/watch?v=VuUXNAtwWS4 That's a big challenge, but his enthusiasm is evident.

RE: Section of I-95 collapses after fire burns under overpass...

If backfilling seems like they could install a couple of very large culverts to save material and allow access for construction vehicles.

RE: Section of I-95 collapses after fire burns under overpass...

A tanker burned under an I-70 EB bridge in Columbus Ohio a few years back. It was reinforced concrete and did not collapse but heavily damaged requiring closure and replacement. I think it was finished in just a few weeks. When you look at the section it stands out a little and seems somewhat hastily built, which it was.

Brad Waybright

The more you know, the more you know you don't know.

RE: Section of I-95 collapses after fire burns under overpass...

Second video posted by Sym P.le

"Highway to Hell" playing. LOL

Regards

Mike

The problem with sloppy work is that the supply FAR EXCEEDS the demand

RE: Section of I-95 collapses after fire burns under overpass...

Compaction of backfill that deep seems like it would take a very long time. I have seen road construction where the road bed is excavated instead of compacted and filled with lightweight cellular concrete. Perhaps they could pour the cellular concrete between sheet pile to minimize the amount of material required.

RE: Section of I-95 collapses after fire burns under overpass...

We have CLSM which is a low strength concrete used for fill purposes...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik

RE: Section of I-95 collapses after fire burns under overpass...

Ok, that is cellular concrete. It uses glass microspheres to reduce the weight of the mixture. I guess it's buoyant in unstable soils so with excavation it can be used in place of compaction.

RE: Section of I-95 collapses after fire burns under overpass...

No it’s not LCC. The article said they backfilling with straight glass.

I’ve heard of AeroAggregate in the past couple of years as a new aggregate. I guess they found their big break.

RE: Section of I-95 collapses after fire burns under overpass...

If I recall, AeroAggregrate is produced in Philly. I've tried specifying it before and it always gets substituted because of the shipping cost.

RE: Section of I-95 collapses after fire burns under overpass...

Yeah, in the article it says that they manufacture it just south of Philly.

RE: Section of I-95 collapses after fire burns under overpass...

Well, it has been five days and there still is no mention of the driver(s)??? name, identity or even the number of human remains..

What company owned the truck ? ... Was gasoline being transported ? .....Was this a regular fuel delivery ?... Have there been other accidents on this ramp before ??? ..... No obvious details are being released ..

I still smell sabotage ....


A complete report scheduled for release first quarter 2024 ..

MJCronin
Sr. Process Engineer

RE: Section of I-95 collapses after fire burns under overpass...

Per CBS News:
"Who was the driver of the tanker truck?
Police asked news crews to not livestream helicopters overhead while investigators sifted through the wreckage in search of human remains, which were recovered Monday afternoon. The driver was identified as 53-year-old Nathan Moody of Merchantville. He was a father of three. 2 days ago"

About the company: https://www.inquirer.com/news/tk-transport-i95-clo...


RE: Section of I-95 collapses after fire burns under overpass...

3
I believe the trucking company was identified, including a brief media interview. If memory serves, it was a local company that delivers gasoline and diesel to stations in the local area. I'm not going to try to find the video again, as I don't believe it's all that necessary for the discussion; I'm pretty sure it was a local media outlet on YouTube, if anyone really wants to find it.

It's pretty clear to me, that it was just a local trucker that ended up too fast for the curve as it tightened under the bridge. No grand conspiracies, just a standard truck rollover in a curve. Probably either driver error (simple loss of concentration or distraction), or equipment failure. RIP Mr Moody, I don't believe you intended to cause harm.

RE: Section of I-95 collapses after fire burns under overpass...

The live feed from the Milnor on-ramp is up. I just watched them remove one of the steel beams from the southbound side. There's a huge pile of dirt in the middle of the gap, and an excavator has been loading it into a dump truck. The truck is only gone for a few minutes, and it always looks to be the same truck, so the dump site must be pretty close. I've no idea where the pile of dirt came from.

I was expecting more activity. I hope the pace picks up soon.

They're stockpiling the foam-glass fill on the I95 roadway near the gap. That area isn't visible from the live feed. https://www.youtube.com/watch?v=jxJS8cOfX8g There are good shots of the material in the video.

RE: Section of I-95 collapses after fire burns under overpass...

I'm not sure how current it is, but the Google satellite view shows a construction site for what looks to be an on-ramp on the northern side of I-95 from Cottman Ave. It would make sense that they could be using that construction site for logistics.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
They're going to have to build some sort of cofferdam or retaining wall, to contain the material under that part of the roadway which they're going to temporarily 'reconstruct'. It appears that there's four-lanes going in each direction and the report was that they were going to build a temporary six-lane segment. Not sure how that will be located relative to the existing lanes, that is, in the middle so that they won't need to divert traffic from one side to the other, or all on one side giving them more room to rebuild the lanes, at least a couple at a time.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

In the video R46 posted above, it says they are going to do 3NB & 3SB for the inner lanes temporarily while the reconstruct the outer lanes. Then switch once finished to complete construction of the inner lanes.

RE: Section of I-95 collapses after fire burns under overpass...

The damaged concrete abutment is drastic.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)

Quote (jerseyshore)


In the video R46 posted above, it says they are going to do 3NB & 3SB for the inner lanes temporarily while the reconstruct the outer lanes.

That would make the most sense as it would require the least amount of rerouting, as I speculated in my first suppositions above.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

The big pile of dirt was originally along the base of the south abutment. You can see the lower part was protected from the fire. There's a trench along the base, and they're currently digging a trench along the base of the north abutment. Looks to me like they're going to demolish and replace both of them from the top of the pilings up. It'll probably be a while before they fill the gap and pave the temporary roadway. What a mess.

RE: Section of I-95 collapses after fire burns under overpass...

Where did the photo in Sym P. le's post above come from? It doesn't look much like the north abutment in the live feed, which is mostly smooth except for several areas on the near end below the northbound lanes.


There's been a lot of activity this morning, including the arrival of a huge conveyor boom to distribute the fill. Maybe they're going to leave the abutments after all.

RE: Section of I-95 collapses after fire burns under overpass...

The Philly Inquirer link that you posted.smile

RE: Section of I-95 collapses after fire burns under overpass...

Leaving the remains of the abutments now, saves some time, as they so not need to be concerned with the dirt behind the abutments being unsupported while the fill is being placed. It may complicate the reconstruction a bit, but as the abutment demo for the reconstruction can now be carefully designed, it can be part of a more normal construction project, where the traffic impact will be better managed.

RE: Section of I-95 collapses after fire burns under overpass...

It is fascinating to watch the construction process. They appear to be using a weldable mesh material, about 10' by 15' or 20' in size to anchor the entire structure together. First a layer of this mesh was laid down, with the end two feet or so bent upwards vertical, but the rest lying flat. The vertical ends were welded to vertical rods to keep the ends vertical. Then the fill was added, leveled, and tamped, with the weight of the fill anchoring the mesh sheets, including the "ends" (or sides if you will). Once the first layer (approx two feet) was completed, another layer of mesh was laid down, again with the end two feet or so bent vertical, more vertical rods were welded in place, and the process repeated. They are progressing about one two-foot layer every two hours (so about 12 feet so far in about 12 hours). With what appears to be about 16 more feet to go, they should be ready to begin applying the final top layer sometime Sunday evening or so. It is just amazing to watch this process, because it is the weight of all of the fill that will (hopefully) keep the fill in place. Fascinating.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
Well, that would avoid have to built cofferdams/retaining walls. In essence, this will result in an all but 'solid' foundation that will have the smallest possible footprint, leaving the most room on either side, allowing them space when it comes time to start to construct the permanent replacement lanes, from the sides, as it were, inward.

Here's a news item with a live video-feed showing the work under way:

https://6abc.com/when-will-i-95-reopen-gov-josh-sh...

Also watch the news clip in the item above as it provides a good explanation as to how the reconstruction will proceed.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

Typical reinforced earth process. Highway construction crews do it all the time, both for temporary and permanent works. With permanent works, the facing is concrete panels.

RE: Section of I-95 collapses after fire burns under overpass...

Youtube page linking to the live stream https://www.youtube.com/@PennsylvaniaDOT/streams

The cross section described i similar to this detail. Continuing the mesh across the entire fill area will minimize the work needed to retain the soil as reconstruction progresses.

RE: Section of I-95 collapses after fire burns under overpass...

2
I too am ignorant to this sort of process, but it makes plenty of sense.

A great video from a youtuber here, pitched to be palatable to non engineers but the principle is the same.
https://youtu.be/0olpSN6_TCc?t=339

RE: Section of I-95 collapses after fire burns under overpass...

...mechanically stabilized earth...aka Reinforced Earth...thanks to the French civil engineer, Henri Vidal for his modern-day version from 1960's.

RE: Section of I-95 collapses after fire burns under overpass...

So what happened? Did the truck and tank roll over and or hit something? How did it end up just sitting there and then a fire ensued?

RE: Section of I-95 collapses after fire burns under overpass...

This FGA material is a reinforced, aerated foam, as I understand it. It has been used in PA for several projects, as shown in this PP:
https://www.penndot.pa.gov/ProjectAndPrograms/Cons...

Even with the material constrained from lateral expansion under load as the temporary overpass support, how could this foam with air content act as a stiff, beam like support to the new roadway? Each of the steel sheet capped building blocks, would seem to act like a vertical spring, with the stacking being like springs in series, loweing the rate, no?

I saw the bulk density was listed as only 8-25 pcf, much less than soil.

RE: Section of I-95 collapses after fire burns under overpass...

A couple of observations:
1. many cities have homeless communities living under these overpasses, and one fire per week per city in the rundown RV's parked under these bridges is pretty typical on the west coast.

2. In addition to the steel failures, there is also the issue of thermal expansion and unseen failures of expansion joints and related fittings. In the hurry to re-open I-95 it is hoped that a complete survey of these expansion features is being addressed.

3.Very fast setiing concrete, called geoploymer concrete , is used by the US military to repair runways that were attacked by munitions, and the runways can be re-opened for air landings/takeoffs within 24 hrs.

"...when logic, and proportion, have fallen, sloppy dead..." Grace Slick

RE: Section of I-95 collapses after fire burns under overpass...

KevinK2,

Density doesn't necessarily determine strength. They have experience in using this material in pavements.

RE: Section of I-95 collapses after fire burns under overpass...

Hokie66,

Agree. But it's light weight because it contains air, which is compressible based on the primary foam material. They advertise you can buy standard open cell material, or closed cell versions, cells being air pockets.

I'm not concerned about strength so much as stiffness. This stuff has many applications for roadways where the total material height is limited, but I have not seen it stacked this high to offer sole support for an elevated, high traffic interstate. The advertse it for "bridge abutments", that's different. The higher the stack, the lower the spring rate in compression.

The aggregate offers excellent shear stability for retaing walls, etc.

The latest video shows what looks like massive concrete slabs, stacked on ends, likely to cap off the current stack.

I hope it works as planned,
Debbie Downer

RE: Section of I-95 collapses after fire burns under overpass...

Yes, stiffness is a legitimate concern. But all pavement materials contain air, and are compressible to a certain extent. I also hope it works.

RE: Section of I-95 collapses after fire burns under overpass...

True about pavement materials. But typical crushed rock/stone, imho, will be a stiffer bed in compression than even a compacted layer of this material:

https://images.squarespace-cdn.com/content/v1/6157...

From the literature:
1.1 Production of foamed glass
Foamed glass is produced industrially by treating cleaned glass particles. These glass particles are
ground into a powder of under 0.1 mm and mixed with a foaming agent. The powdered glass is then
spread onto a conveyor belt and then slowly passed through a furnace. The furnace heats the
powdered glass to a temperature of 900 °C. This causes the glass mass to expand to five times its
original size and it subsequently hardens into foamed glass. 92 % of foamed glass´s composition is
air bubbles
. As the foamed glass cools, it breaks up into pieces and forms foamed glass aggregate.

I assume 92% by volume.

Applications:
• Many uses for lightweight aggregates
• Embankment fill over soft soils
• Retaining walls
• Bridge abutments
• Reduced lateral load of backfill
• Lightweight fill over culverts and utilities
• Under foundation slab insulation and drainage
• Insulation layer
• Horizontal or vertical
• Greenroofs

The primary advatages of this material is light weight, and shear stability as was the original heavy product. Perfect for retaining walls.

I have not yet found another application like this one on I95. Classic beam with pinned ends on an elastic foundation.


RE: Section of I-95 collapses after fire burns under overpass...

How are they going to remove the aggregate and reinforcement materials when they are no longer needed? I can't see how they could lift it over the active roadways or load it onto trucks between the active roadways. That leaves "mining" it by tearing into the sides of the pile from below the newly constructed bridges, and letting the pile collapse as it's carried away.

RE: Section of I-95 collapses after fire burns under overpass...

This image may help understand the project:

https://assets3.cbsnewsstatic.com/hub/i/r/2023/06/...

Originally it was at least 4 lanes each way. The temporary support is under the central 2 or 3 lanes each way. Once completed, construction will begin on permanent repairs to those outer lanes on each side. When completed, the central temorary lanes will be rebult with permanent support:

"When eventually constructing the (temporary) bridge, there will be six lanes — three for northbound and three for south in the center area of the “void”, according to Pa. Transportation Secretary Mike Carroll.

The outer 35 feet will be under construction and not impact traffic. Once completed, the reconstruction will then move toward the center of the bridge."



RE: Section of I-95 collapses after fire burns under overpass...

SGW1009,

While observingthe creation of the large "bricks" of the light fill, fully encased in a welded on wire mesh, did you observe a step to compact the material to a denser condition? Or mabe it was precompacted?

The PP I linked on 19 Jun 23 14:41, suggests compaction is necessary for minamal rigidity, going from a loose 15 pcf to 18 pcf.

RE: Section of I-95 collapses after fire burns under overpass...

The rapid response to get traffic moving again is admirable. From this daily update link:

https://www.penndot.pa.gov/RegionalOffices/distric...

"7:40 p.m. on June 18, Today marks one week since a vehicle fire led to the collapse of a section of Interstate 95 in Philadelphia .... the Shapiro Administration expects the roadway will reopen within the next two weeks."

"Crews continue to make headway on the interim roadway, which will open temporary travel lanes on I-95, three in each direction, while work proceeds to rebuild the outer sections of the permanent bridge. The process to fill in the roadway in the area of the collapse with a specially designed, Pennsylvania-made recycled glass aggregate is expected to conclude within the next day or two. Once fill is complete, eight inches of modified sub-base will be installed, edge and median barrier will be installed, and the transition between the new roadway and existing lanes will be prepped. Paving operations will begin soon after. Equipment is being staged and mobilized for next steps and work continues."

A lot of progress in 1 week, but was enough engineering put into this unique application of this super light fill ? Politics has interfered with engineering before, with a space shuttle launch when engineers said it was too cold for the critical o-ring seals.

RE: Section of I-95 collapses after fire burns under overpass...

I saw men pushing around what looked like small compactors with handles, and some rubber-tracked Bobcat sized loaders going back and forth. I never saw anything larger being used, and none of what I watched looked like they were compacting the entire area, just the sides, ends, and spots here and there. It didn't appear that the layers were very flat. The track loader would pitch noticeably as it moved around over uneven places.

It looked to me like they were only using large pieces of black fabric rather then wire mesh for most of the areas. It was really flexible, easily folded, and appeared to be pretty light by the way it was being handled and spread out.

RE: Section of I-95 collapses after fire burns under overpass...

As Retiredat46 stated above, compaction was limited to two Bobcats and two handheld vibrating compactors. That is the limit of the compaction. Also, the black fabric is some kind of metal mesh, because once in place it was welded to vertical bars (maybe 6 foot in length each). So the fabric is definitely very flexible but also very weldable.

RE: Section of I-95 collapses after fire burns under overpass...

They're putting the L-shaped concrete side barriers on the near side of the filled area right now. We won't be able to see any of the work being done there after all the pieces are in place. Rats!! On the plus side, we'll have a plain gray background for watching the new bridge being built. Hooray!!

RE: Section of I-95 collapses after fire burns under overpass...

The I-95 webcam has been relocated to the top side of the bridge, looking south(?), so once again we have a reasonably good view of what they are doing. Thank you PENNDOT. We are now looking in almost the opposite direction. Visible is the north side of the fill. Before we were seeing the south side of the fill.

RE: Section of I-95 collapses after fire burns under overpass...

Some compaction is better than none. The hand pushed one is in view now, being used to compact a new, dark material that was deposited in a steady flow from hose held high by a crane, similar to filling poured foundation walls for a new house. It looks like it's limited to the edge of the temporary support.

Hard to believe that what we now see from the new camera angle, of prep'd roadway, will support 3 lanes in each direction.

RE: Section of I-95 collapses after fire burns under overpass...

From Aero Aggregates PP Presintation about Compaction of fill:

https://res.cloudinary.com/engineering-com/image/upload/v1687309591/tips/UL-FGA_1_rrcfpq.pdf

https://res.cloudinary.com/engineering-com/image/upload/v1687309365/tips/UL-FGA_2_rj9ibt.pdf

For roadway support, appears to be bulk thicknes limited to 12" if using a push compactor, but it appeared to be used on the full 24" blocks.

And for the full 24", 600-1000 psf, 2 passes "with a tracked excavator or dozer"

RE: Section of I-95 collapses after fire burns under overpass...

That's going to be a very tight 3 lanes in each direction for sure.

RE: Section of I-95 collapses after fire burns under overpass...

PA Governor said today that the roadway will be open this weekend. What an effort if that holds true.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)

Quote (KevinK2)


PennDOT new live video...

And notice how the contractor has strategically placed his 'shingle' winky smile



John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

Latest video shows one lane going north has opened, on the far side of the original highway. Good news. Now it's 2 lanes. I think it's because those lanes had been used to bring many semi's full of aggregate to the site, and that part of the job is done.

Some degree of rain is predicted by noon, continuing for the next week. They have been lucky with dry weather so far. It's good that the top of the aggregate is now sealed with the ~ 1 foot thick compacted black layer, and other coveings.

The massive L-shaped outer temporary highway barriers look like the bottom of the L will be under the underlayment and new pavement. Not sure if thay are keys to each other at the joints.

RE: Section of I-95 collapses after fire burns under overpass...

What KevinK2 is seeing in the ABC7NY live feed is traffic on the Milnor Street onramp which is just to the southeast of the work area.

RE: Section of I-95 collapses after fire burns under overpass...

Retiredat46, Thanks for the correction. I guess we didn't see that from the other camera angle.

RE: Section of I-95 collapses after fire burns under overpass...

Workers have been cleaning out the expansion joint that runs across the highway from right to left on the near (north) side of and several feet away from the gap. They've been digging into, blowing, and sweeping all along the joint. Maybe they're preparing for an inspection of the joint that was mentioned by davefitz on June 19.

RE: Section of I-95 collapses after fire burns under overpass...

So great to watch this come together so quickly this past week. Really makes you even more angry how lovely it is to have a local highway under construction for like 6 years with barely any progress.

RE: Section of I-95 collapses after fire burns under overpass...

jerseyshore, this is a herd of union workers working overtime, 24/7. This was a no-bid job, at a huge expense. I agree typial government contracted highway work seems to take longer than necessary.

On the otherhand, I witnessed a ~large commercial parking lot being repaveded starting with a "road eater" removing all old pavement. It was like watching an ant farm, related big machines appeard on a "just in time" basis, rollers & pavers dissappeared when done, all going to another jobs site in progress. No worker was ever idle.

RE: Section of I-95 collapses after fire burns under overpass...

The first concrete truck has arrived on scene.

Edit: Concrete truck was only there a short while, and there was only one of them. Reason unknown.

RE: Section of I-95 collapses after fire burns under overpass...

When MI rebuilt I-75 through Detroit that work was 24x7.
It sure didn't take long.
More proof that time and money are fungible.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Section of I-95 collapses after fire burns under overpass...

Currently pumping a black material from a dangling hose, and using the bucket of the big CAT excavator like a wheelbarrel to help material placement.

Another ~1 foot layer of black material topped the light wt aggregate stack, and was compressed, followed by a similar grey layer. Now black again. None appeared to be concrete so far.

Update, 4pm, now they appear to be adding more foamed glass aggregate and compacting it with a small doser with tracks, similar to their advertised underlayment for new roads.

RE: Section of I-95 collapses after fire burns under overpass...

It looks like it's just a 6" step to get onto the existing road from the work area, suggesting concrete or asphalt comming soon. But rain is comming, latest update is steady rain starting at mdnight and all day Thursday. Not good.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
Speaking of I-75 going through Michigan, how long did it take to build, then repair and rebuild, the infamous Zilwaukee Bridge over the Saginaw River back in the 80's?

https://en.wikipedia.org/wiki/Zilwaukee_Bridge

In the end, it took over nine-years to finish the bridge, replacing a drawbridge which opened once or twice a day for a sand dredge bringing casting sand from Saginaw Bay to a GM foundry. The irony is that during the time when they had shut down the construction, fired the original contractor, hired a new one, repaired the damage and finally restarted the construction (see the 'History' section of the above Wiki article), GM had decided to close the foundry, meaning that now the old drawbridge would've needed to only be opened four or five times a YEAR.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

Yeah John, at least when I was growing up in MI, in the '60's and '70's, that ******* Zilwaukee draw bridge always seemed to open on Friday and Monday afternoons/evenings of holiday weekends. Grrrrr.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
Where in Michigan did you grow up?

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

Farmington.
We built a cottage on Otsego Lake near Gaylord; used to go up there a lot; still have it in the family.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
My wife and I are from Lewiston, about 30 miles East of Gaylord. We used to drive to Gaylord as it was the closest movie theater back when we were in high school. Both my wife and I still have cousins in the area. And for about 17 months, in 1986-87, we lived in West Bloomfield and I worked in Farmington Hills.

Where in California are you located?

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

At 8:41pm they are compacting again, and just began paving the far side. The first dump truck of black top is loading the paver now.

They have been using push compactors alot during last few hours. They did nothing close to this building up the lower support system, where it was also need, imho.

RE: Section of I-95 collapses after fire burns under overpass...

"Under the leadership of Governor Shapiro and Secretary Carroll, crews have worked around the clock to reopen the roadway safely and as quickly as possible". Too soon for taking bows.

Kevin Kelleher, PEME
Internal Mechanical Eng'g Consultant
DuPont ESD Specialists

RE: Section of I-95 collapses after fire burns under overpass...

I'm assuming they didn't go crazy with compaction to save time and get this stretch reopened asap. A little dip in the roadway if it settles is probably not a big deal right?

RE: Section of I-95 collapses after fire burns under overpass...

I don't think they came close to properly compacting the lower support. SGW2009 descrbed the process he observed. Souded like they built ~ 10 ft x 18 foot wire mesh boxes, open at the top. Fill it with raw material that OEM said each piece was 92% air by volume, not counting the voids when filled to a 2 foot depth in the wire boxes.

He said the compaction was a bit hap hazzard.

I think over time, with occasional bumper to bumper 20-30,000 lb semis riding over with relatively resricted slow traffic on 3 lanes each way, steady setteling will be an issue.

From my prior comments from OEM about recommended compaction:

For roadway support (not an overpass), appears to be bulk thicknes limited to 12" max if using a push compactor, but it appeared to be used on the full 24" deep blocks.

And for the full 24", 600-1000 psf, 2 passes "with a tracked excavator or dozer"

Kevin Kelleher, PEME
Internal Mechanical Eng'g Consultant DuPont ESD Specialists

RE: Section of I-95 collapses after fire burns under overpass...

A settled roadway is better than no roadway. Can't be much worse than the rest of the roads in this area. If it settles a lot they can just add more pavement overtop. Semi-temporary quick fix anyway.

RE: Section of I-95 collapses after fire burns under overpass...

When dealing with aggregate as large as the foamed glass aggregate being used here, there is not much compactive effort needed. Large aggregate is usually dense when placed, and will get denser with a little compaction. In fact, just driving equipment across the material will help compact it. This goes even more so when dealing with a large fill like this. More equipment as the lifts rise more locking in of the particles.

I also notice a concern with the air content in the aggregate. That air will not move or migrate unless the actual piece of aggregate the air is locked in physically breaks. This is not like a soil matrix where the air voids can be compressed. If anything, too much compaction will break the particles down making much more settlement than compacting less. I believe this is the case if the manufacturer recommends using tracked equipment for compaction. Tracked equipment can't be used to compact because the ground pressures are too low. Tracked equipment in this case will lower the load on the aggregate to prevent breaking, while still giving enough overall stress increase in the fill to lock in the large particles. I believe the techniques used here were a tradeoff, minimal compaction to lock in the particle but not break them. Plus this is an temporary emergency. This fill is not permanent.

RE: Section of I-95 collapses after fire burns under overpass...

Milliontown,
The process of building this light weight support was observed. Little effort was made to compact each 2 ft high "oversized brick" unit, capped with wire mesh. I think the voids you create between each of these odd shaped pieces is much higher than lower grades of crushed rock typically used in roadway construction.

When the minimally compressed material is compressed in final use, edges of each piece will be crushed, adding to settling. The low compression resistent properties listed by independent labs, whose links I have posted, were done per ideal conditions, with material in a cylinder, constrained in radial and vertical (bottom) directions, with a close fitting piston doing the compressing. Not like this real world.






Kevin Kelleher, PEME
Internal Mechanical Eng'g Consultant DuPont ESD Specialists

RE: Section of I-95 collapses after fire burns under overpass...

Hello,

I live near Atlanta and in addition to the I-85 fire that took out the bridge several years ago, we just had a 20 month closure of Cheshire Bridge road. A fire started under the bridge which then damaged and ignited a gas line which destroyed the bridge. From what I read, the bridge was steel and built in the 1930s.

Just like the I-85 bridge, no one really faces the consequences except the tax payer.

Kyle

RE: Section of I-95 collapses after fire burns under overpass...

Milliontown, I hope this video by the Foam Aggregate CEO gives you a better understanding of this Foamed Glass Aggregate that is being used, and the voids created when used like this app w/o significant compaction. Each cube has a common, 1-1/2" thickness, based on the mfg'ing belt conveyor process: https://www.youtube.com/watch?v=3mdDeKTKB1I

Also, compaction is considered essential by AeroAggregates when the material is used as underlayment for roads, the only advertised application where it is supporting a load, per the company's video used by Penndot: https://www.penndot.pa.gov/ProjectAndPrograms/Cons...

Kevin Kelleher, PEME
Internal Mechanical Eng'g Consultant DuPont ESD Specialists

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
From looking at the live-stream below, it would appear that they're putting the finishing touches on the new road bed. If their goal is to have traffic crossing this temporary roadway by Saturday, I would say that they're going to make it with time to spare.

https://livestream.com/accounts/11892034/events/10...

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

The far side looks completed, half the near side needs another layer and the paving machine is ready to start, couple of dump trucks full of paving material are already backed up.

Still a lot of work with the heavy barriers to create the final roadway, with transitions from multiple lanes to 3 each way.

Kevin Kelleher, PEME
Internal Mechanical Eng'g Consultant DuPont ESD Specialists

RE: Section of I-95 collapses after fire burns under overpass...

I'm fascinated by what they are doing now...a sweeper truck is making passes cleaning up the road surface; so far, it's been 4 trips over the same section...and the guys with brooms are sweeping more dirt onto the area that the truck has just covered. No, wait, it's 5 times so far...I have to admit, this is better than watching golf!

RE: Section of I-95 collapses after fire burns under overpass...

Sweeping means they're getting ready for lane marking. I wonder how far back the transitioning from six to three lanes will begin, and if there will be any limitations on vehicle weight. I'm guessing they'll set the speed limit at 45 for the narrowest part, but enforcement will be very difficult.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
If traffic is as heavy as they claim it is along that section of I-95, it'll probably be so heavy that speeds will already be pretty slow.

From the livestream, it looks like they've got the T-rails all in place to funnel the traffic down to the three-lane section on each side. Not sure haw far back they stretch but you can see that they're at least up to the narrowed section.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
I was just watching the livestream and it looked like a white car was driving on what I assume was the Northbound side and it was being chased by a police car with it's red and blue lights flashing, catching-up with the white car just past the new section of roadway.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

I just saw the painting truck go by applying the last of the lane markings. I watched several work trucks go by, too. People driving standard full-size pickups should be pretty comfortable as long as they're not sandwiched between two big rigs. For someone like me who hasn't driven on an interstate in several years or over fifty mph in several months, it might be a white knuckle experience.

RE: Section of I-95 collapses after fire burns under overpass...

Quote (KevinK2)

Milliontown, I hope this video by the Foam Aggregate CEO gives you a better understanding of this Foamed Glass Aggregate that is being used, and the voids created when used like this app w/o significant compaction.

I am aware of AeroAggregate and have been before this incident. My job working on Embankment Dams has given me a lot of experience working with compaction, aggregate, and compaction of large aggregate. Voids will be present for any aggregate. If this were to be backfillled with gravel there will still be voids, same with sand or finer soils. There are also voids present within the aggregate. These voids are trapped within the glass media and cannot move without breaking the entire aggregate block.

As I have tried explaining, these voids between blocks are and always will be present. Compaction of aggregate this large does not need very much compactive effort. The plate compactor being used in the presentation linked imparts a very low compactive effort, and combined with the fact that small of equipment being used on 12" lifts tells me that the compactive effort needed for these aggregate is low. As more material is placed, the lower lifts will also compact. Additionally, I believe the plate compaction shown is just used to lock in the particles on the upper portion of the 12" lift as the lower portion would be locked in during placement and spreading, with some equipment running over it. I believe this to be true for this repair as well, as the equipment being used to spread the material will also impart a compactive effort.

Another thing I have noticed in the presentation is the lack of larger compaction equipment. Again this tells me that the compactive effort needed is low, and that large equipment would actually break down the particles.

Would I have done it this way on a dam? Maybe not, but again this is an emergency temporary fill to get lanes open.

RE: Section of I-95 collapses after fire burns under overpass...

Milliontown,

"My job working on Embankment Dams has given me a lot of experience working with compaction, aggregate, and compaction of large aggregate."

If that included using the this specific aggregate, emabankment dams is an approved use of this material, using the layered approach. It is very stable in shear.


"Voids will be present for any aggregate. If this were to be backfillled with gravel there will still be voids, same with sand or finer soils."

I agree on the stable voids within the expanded glass particles. My point was the % voids per cubic foot, vary with aggregate, just like BSC vs FFC intersticial site volume in molecules: "The interstitial site in the BCC iron is smaller than the interstitial site in the FCC iron."

Unlike other aggregate, this suff has a constant thickness of about 1-1/2 inch, which, imho, contributes to less nesting, and larger voids.

"The plate compactor being used in the presentation linked imparts a very low compactive effort, and combined with the fact that small of equipment being used on 12" lifts tells me that the compactive effort needed for these aggregate is low."

Two 12" lifts were only used when they created a layered topping to the finished, wire caged support system, starting with ~12" compacted apparent black top, then compacted foam aggregate, another black top, then foam, final blacktop. This may have been just along the outer sides, with less layers in the middle.

Those observing the hand pushed compactor during the support buld up noted it was only used when the full ~24" unit rectangle was filled, likely to save time. And when a rubber tracked small tractor ran the length, it was pitching up & down on the irregular fill. This would contribute to even more voids pcf then just a pile of this aggregate.

Without a political deadline established early, and boasted about by Governor Shapiro at every press opportunity, including one with Biden, a better job would have happened.

I still hope it works.




Kevin Kelleher, P.E. (retired)
Internal Mechanical Eng'g Consultant
DuPont ESD Specialists

RE: Section of I-95 collapses after fire burns under overpass...

We're about to find out how well it'll perform. They just had the reopening ceremony at the construction site, and traffic will soon start flowing with no additional weight restrictions.

Let's investigate setting up a GoFundMe page to buy PENNDOT a decent camera and related equipment for their live feed. What they have is pathetic with the blurriness, herky-jerky motion, and frequent test screen performance.

RE: Section of I-95 collapses after fire burns under overpass...


Design Loading Assumed ?

Most states like Delaware, limit semi trailer weight to 68,000 max for an 18 wheeler, with 34,000 lbs at each double axle. In a ~worst case senario, 6 rows of slow moving traffic, with bumper to bumper semis, that's 384,000 at center span possible, made worse if semis are before & after these 6 ones centered.

Average/typical loading will be much less.

Kevin Kelleher, P.E. (retired)
Internal Mechanical Eng'g Consultant
DuPont ESD Specialists

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
Yes, as seen on the livestream, traffic is flowing on what I think is the Northbound lane. I didn't see anything in the other lane and you still see lots of traffic on the surface street running parallel to the what I think is the Southbound lane. Well, this means that at least for one lane, they're open a day early as the last report that it was scheduled for the weekend.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
And the traffic appears to be moving at normal speeds, but it's not very heavy yet. And it appears that there's no restrictions as I've seen 18-wheelers passing in the lane that's open. And now that traffic is moving over the new roadway, it appears to pretty close to normal width lanes, so it looks like the did a good job.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
Traffic is now moving in both directions and it's starting to get heavy. There are what looks like some DOT vehicles monitoring traffic near repaired roadway.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

I looked at the live feed on my tablet where I can easily zoom in for a closer view. It's not encouraging. The edges of the asphalt appear to be breaking up where it meets the concrete in the places where the tires run most of the time. The worst places are several inches wide and deep and over a foot long. I wish someone else would take a look to confirm what I'm seeing or tell me I'm wrong.

RE: Section of I-95 collapses after fire burns under overpass...

(OP)
It's starting rain and it's not very clear when it comes to details.

John R. Baker, P.E. (ret)
Irvine, CA
Siemens PLM:

The secret of life is not finding someone to live with
It's finding someone you can't live without

RE: Section of I-95 collapses after fire burns under overpass...

The camera system being used may be fairly high resolution, but there is a tremendous amount of compression being done to keep the required bandwidth low, so the pictures we are getting are fraught with artifacts.

RE: Section of I-95 collapses after fire burns under overpass...

The location that look odd to me is longitudinal portion of the joint that is right in the left-hand tire path in the right lane.
But until it dries off it will be difficult to tell if there is really an issue.
Even if they have to close it Sun night for resurfacing, they will still be way ahead of the game.

= = = = = = = = = = = = = = = = = = = =
P.E. Metallurgy, consulting work welcomed

RE: Section of I-95 collapses after fire burns under overpass...

The places that looked iffy earlier now look fine. I think sgw1009 must be correct about it being artifacts of the video feed. Thanks for the explanation.

RE: Section of I-95 collapses after fire burns under overpass...

Just Posted
NTSB Ongoing Investigation

Mode Highway

Investigation No HWY23FH014

Event Date 6/11/2023

Location I95 Philadelphia, PA


Quote (https://www.ntsb.gov/investigations/Pages/HWY23FH0...)

What Happened
​​​​This information is preliminary and subject to change. Release date: 29​ June 2023

​​On Sunday, June 11, 2023, about 6:17 a.m. eastern daylight time, a 2017 International truck-tractor in combination with a 2004 Heil Specification Package 406 tank-trailer (combination vehicle), operated by a 53-year-old driver, was exiting Interstate 95 (I-95) northbound on the Cottman Avenue off-ramp in Philadelphia, Pennsylvania. At this location, I-95 was an eight-lane divided highway with four lanes each in the northbound and southbound directions.

The combination vehicle, operated by an affiliate carrier leased to Penn Tank Lines, was transporting about 8,500 gallons of gasoline from Wilmington, Delaware, to a gas station located on Oxford Avenue in Philadelphia. The posted speed limit on I-95 in the vicinity of the crash was 55 mph, and the Cottman Avenue off-ramp was posted with a 25-mph speed limit and truck rollover warning sign.

The truck driver was unable to maintain control of the combination vehicle on the off-ramp. The truck rolled over and subsequently caught fire under the northbound lanes of the I-95 overpass.

As a result of the rollover and subsequent fire, the driver was fatally injured. The fire caused the northbound lanes of I-95 to collapse onto the Cottman Avenue off-ramp. The southbound lanes of I-95 were significantly damaged by the fire.

​Parties to the National Transportation Safety Board (NTSB) investigation include:

​Federal Motor Carrier Safety Administration
Pipeline and Hazardous Materials Safety Administration
Pennsylvania State Police
Pennsylvania Department of Transportation
City of Philadelphia, Pennsylvania

All aspects of the crash remain under investigation while the NTSB determines the probable cause, with the intent of issuing safety recommendations to prevent similar events.

RE: Section of I-95 collapses after fire burns under overpass...

Quote (KevinK2)

Without a political deadline established early, and boasted about by Governor Shapiro at every press opportunity, including one with Biden, a better job would have happened.

Aww it hurts you so much to actually see a competent government doing what a government should do. :)

This was handled by lots of experts outside of the lane PENDOTT or whatever. And certainly more capable than the opinions of me or a so called mechanical engineer.

RE: Section of I-95 collapses after fire burns under overpass...

Six months after a truck fire collapsed an I-95 bridge in Philadelphia, traffic moved from the temporary roadway to the recently completed outer lanes ahead of schedule on Nov. 6.

Nov 6 23 PenDOT update (Linked page is regularly updated with progress)
Traffic shifted from the temporary roadway onto the newly completed outer travel lanes of the new permanent bridge on Interstate 95. Crews will move and reset temporary construction barriers and repaint lane markings before shifting three lanes of northbound vehicles and three lanes of southbound vehicles onto the outer sections of the new span.

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