Francis Scott Key Bridge in Baltimore collapses.

[beefeater33]

An article on prevention of bridge collapses.

How a $3m structural 'flaw' led to catastrophic collapse of Baltimore bridge - Times of India

The operators of the Dali cargo ship issued a mayday call that the vessel had lost power moments before the crash, but the ship still headed toward the span at “a very, very rapid speed," Maryland governor Wes Moore said. The 985-foot-long (300-meter-long) vessel struck one of the 1.6-mile...

timesofindia.indiatimes.com

When they put it back they’ll protect it from a similar cargo ship strike.

One question I’d like answered.

The Key bridge was a steel truss bridge with reinforced concrete supports.

Those supports had a lot of weight pressing down on them and were sunk quite a ways deep.

How did a 100,000 ton ship move a concrete support, enough to bring down the bridge?

Normally the support wins any contest between a ship and a bridge, I’d think.

The bridge supports were designed to do just that- support the bridge. They weren't necessarily designed for lateral loads, but more for downward pressure loads.
The sheer mass of the moving ship created an enormous amount of kinetic energy and would push a relatively small concrete structure out of it's way..........

 

[ssjones]

It's a great tragedy and the iconic bridge here in MD is no more. Hopefully it gets rebuilt quickly and in a safe manner. A couple things stand out to me.....
1) having traveled across that bridge recently I am keenly aware of how high it was (something that is hard to discern in the night-time video of the crash).
2) I am also keenly aware of how quickly life can change / be taken away
3) traffic patterns here will change DRASTICALLY. This is I-695, the Baltimore Beltway. This bridge is the fastest route for many to get around Bmore to Philly and points north. Now, one of the east coast's biggest and busiest shipping ports that delivers goods throughout the midwest is presumably closed for awhile and the beltway is hindered. Trucks can still go I-895 through the tunnel, but due to size restrictions much truck traffic will have to travel around Baltimore the opposite way. This is a big deal for Washington, DC too due to the amount of daily commuters between the Baltimore and DC metro area. It's a traffic mess.

I just hope that they can recover the remaining missing individuals to offer some closure to families.

I've also driven that bridge countless times and I can't comprehend the power it took to knock it down in seconds. Watching those last few cars and a tractor trailer cross seconds before disaster is frightening. The bridge looks small against the contrast of that ship, it was not.

You are right, one half of the Baltimore Beltway is cut off, so the remaining half of the circle will have double the volume. Thank god I rarely travel the Beltway to I-95 and the NJ Turnpike these days.

 

[AJL67]

I wouldn't be surprised if the Army Core of Engineers was there quickly was some kind of floating pontoon roadway to ease at least some of the traffic issues, maybe not in that area but somewhere.

 

[ssjones]

I wouldn't be surprised if the Army Core of Engineers was there quickly was some kind of floating pontoon roadway to ease at least some of the traffic issues, maybe not in that area but somewhere.

I'm sure as hell avoiding that kind of contraption. But, I think that has been done in war countries. Safely, dunno about that...

 

[prairiedruid]

Pontoon bridge is not possible since it is a shipping channel.

 

[Streeper541]

I saw on social media that this ship the "Dali" has history with this, seems like it ran into the wharf at another terminal and cause severe damage too. Things that make you go hmmmmmm

I don't think one thing has to do with the other. Ships, bump docks all the time. It's not as smooth a process as the public might think.

Could have been an entirely different crew back in 2016. Certainly a different pilot. I'm sure different weather conditions. All those things play factors.

How did a 100,000 ton ship move a concrete support, enough to bring down the bridge?

Seems like an exercise in basic physics to me... Newton's second law of motion discusses the relationship between force, mass and acceleration (F=MA), as well as the nature of momentum (P=MV) ... or as we say in the Coast Guard, the gross tonnage rule was in effect.

 

[gubbyduffer]

It' a prize fight between a 21st century economy of trade and commerce vs 1970's infrastructure project. There would only be one winner, although I was surprised and shocked at just how quickly 1970's infrastructure folded. Like watching Arnold Schwarzenegger bump into a dry spaghetti tower.

 

[AJL67]

I'm sure as hell avoiding that kind of contraption. But, I think that has been done in war countries. Safely, dunno about that...

I've driven on them in convoys of full loaded hummers, they are more sturdy than you'd think, or at least more than i thought about going over one. lol

Pontoon bridge is not possible since it is a shipping channel.

Yes, that's why i said mb not in that area but somewhere, they most likely have to do something or traffic will be screwed for years.

 

[Briar Lee]

I was just reading how the eight construction workers fell 185 feet to the water, and one is critical, six are dead, and one is lucky.

As incredible as it sounds, did the Dali knock a double concrete support over 150 feet high clean over into the channel?

Where did the support go?





The two radio towers are protected by “bumpers”.

And in front of the knocked over double support is some kind of buoy or warning structure. On the double support still standing they are on not sides.

The approaches to the steel truss bridge and all their supports are still standing.

Once they get all that steel and concrete out of the channel, I’d be surprised if they span that again with a steel truss bridge.

Here is a photo of an 81 million dollar brand new bridge at Rocheport over the Missouri River. Actually it’s half a new bridge. The old one was a steel truss four lane bridge finished in 1965. They built the modern bridge in about a year and then blew the old steel truss bridge in the river six months ago, cleaned that out, and there’s an identical new four lane going across the place the old one was, they are building.

It’s a major I-70 twin four lane bridge, but no doubt it’s easier to span the Missouri than a tidal bay.

But the principles should be the same.

 

[jpmcwjr]

Listening now to the NTSB slive report, and Ms. Homedy has a speaking manner that put me to sleep. Monotone and long winded.

 

[Briar Lee]

From NTSB

• 12:39 a.m.: Ship departed from the Seagirt Marine Terminal
• 1:07 a.m.: Ship entered the Fort McHenry Channel
• 1:24 a.m.: Ship traveling at a heading of 141 at about 9.2 mph
• 1:24:59 a.m.: Censor data stopped recording, but audio recording continued
• 1:26:02 a.m.: Censor data recording resumed
• 1:26:39 a.m.: Pilot made a radio call for tugs to assist
• 1:27:04 a.m.: Pilot ordered an anchor drop
• 1:27:25 a.m.: Pilot radioed that all power was lost and asked for bridge to be closed
• 1:29 a.m.: Ship was traveling less than 8 mph
• 1:29:33 a.m.: VDR recorded sounds consistent with crash, and dash cameras show bridge lights go out
• 1:29:39 a.m.: Pilot reports to Coast Guard that the bridge is down

Xxxx

When you see all those cars zipping across the bridge, the toll operators on both sides had just three minutes warning.

The vehicles that fell in belonged to the eight construction workers on the bridge. If they were out working on pot holes they wouldn’t have had time to escape.

And there was an order to drop anchor.

Wonder if anchor drop was made?

 

[pappymac]

From NTSB

• 12:39 a.m.: Ship departed from the Seagirt Marine Terminal
• 1:07 a.m.: Ship entered the Fort McHenry Channel
• 1:24 a.m.: Ship traveling at a heading of 141 at about 9.2 mph
• 1:24:59 a.m.: Censor data stopped recording, but audio recording continued
• 1:26:02 a.m.: Censor data recording resumed
• 1:26:39 a.m.: Pilot made a radio call for tugs to assist
• 1:27:04 a.m.: Pilot ordered an anchor drop
• 1:27:25 a.m.: Pilot radioed that all power was lost and asked for bridge to be closed
• 1:29 a.m.: Ship was traveling less than 8 mph
• 1:29:33 a.m.: VDR recorded sounds consistent with crash, and dash cameras show bridge lights go out
• 1:29:39 a.m.: Pilot reports to Coast Guard that the bridge is down

Xxxx

When you see all those cars zipping across the bridge, the toll operators on both sides had just three minutes warning.

The vehicles that fell in belonged to the eight construction workers on the bridge. If they were out working on pot holes they wouldn’t have had time to escape.

And there was an order to drop anchor.

Wonder if anchor drop was made?

I wonder what happened during that 1 minute 3 seconds that the Censor data stopped recording.

 

[Pipeoff]

Tragic loss of lives and a hell of a way to get a new bridge. I am glad that I don’t have any stock in the shipping company. Many Captains often lie to the harbor guide about condition of the ship.

 

[jpmcwjr]

The port anchor most surely did drop, but it's like trying to stop your car with your foot at almost any speed.

 

[Briar Lee]

I wonder what happened during that 1 minute 3 seconds that the Censor data stopped recording.

The ship was traveling about half the speed of a horse pulling a buggy at a fast trot.


If the engine quits, and the lights go out, the first thing to do is restart the engine.

 

[jpmcwjr]

The ship was traveling about half the speed of a horse pulling a buggy at a fast trot.


If the engine quits, and the lights go out, the first thing to do is restart the engine.

Yeah, easier said than done! Some have speculated that bad fuel cause the engine to conk out. If so, restarting would be a chore and a half!

You mentioned earlier- did it knock down the big—huge!— support pillar? Must have— I can't see it from any angle.
So glad the damage to the bow area didn't extend to the waterline. Had the ship also sunk, it'd add weeks to the already long repair shedule.

 

[pappymac]

The ship was traveling about half the speed of a horse pulling a buggy at a fast trot.


If the engine quits, and the lights go out, the first thing to do is restart the engine.

If the engine quits you can try to restart the engine.
If the lights go out, you have to restart the electrical generator.
At least when I worked in the engineroom, it was two separate systems. That being said, the steering system was tied into the propulsion system and not the electrical.

The ship may have only been traveling at 8 miles a hour when the engines went out but it's not easy to stop a vessel that size.

 

[tbradsim1]

Cajun observation no pileings bumpers around the mostly traveled center section supports.

 

[Briar Lee]

Cajun observation no pileings bumpers around the mostly traveled center section supports.

Look close. There was something called a dolphin in front of both supports. In 1980 a ship a third the size of the Dali hit the support and the bridge won.

If the Dali had hit the dolphin it would have busted it, but it could have slowed it down, or caused it to veer back in the channel.

Murphy’s law was at work.

Had the engine problems arose five minutes later the Dali would have cleared the Key Bridge.

The tugs had just turned Dali loose.

Five minutes earlier and they’d have towed her back to port.

 

[Briar Lee]

If the engine quits you can try to restart the engine.
If the lights go out, you have to restart the electrical generator.
At least when I worked in the engineroom, it was two separate systems. That being said, the steering system was tied into the propulsion system and not the electrical.

The ship may have only been traveling at 8 miles a hour when the engines went out but it's not easy to stop a vessel that size.

At the Lake of the Ozarks, when a boat gets over about thirty feet long they generally have two engines and two propellers.

I was out once in a friend’s 36 foot Chris Craft Constellation and he lost his starboard engine and we still had a good time cruising back to the dock.

Today, there are 100,000 ton container ships like Dali crossing the world’s wide oceans with just one engine and one propeller,,,,at 22 knots!

What would happen to Dali if she was in the middle of the Pacific in a storm and lost her engine?