100,000 tons moving at 7knots doesn’t stop on a dime, but even without that Baltimore harbor ain’t deep relative to these ships, so all that takes roomQuote:
Originally Posted by present tense
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100,000 tons moving at 7knots doesn’t stop on a dime, but even without that Baltimore harbor ain’t deep relative to these ships, so all that takes roomQuote:
Originally Posted by present tense
They are indeed. 1 acre diamond shaped islands surround the main pilings that can stop/redirect a container ship from hitting them.Quote:
Originally Posted by present tense
The Grace Memorial Bridge, which the Ravenel Bridge replaced, was the exact same kind of bridge as this one in Baltimore that got hit. It was insanely sketchy to drive over as its see-through metal grate deck swayed back and forth in the wind, with only 3 small steel rails separating you from the 150' drop to the water below.
The Ravenel Bridge is what allowed CHS to expand the port to accommodate the biggest container ships and car carriers and is so rock solid you barely know you're 580' feet off the water when you're walking or riding your bike across it.
There's structures in the water (they're called "dolphins" apparently) in front of the piers designed to prevent such a thing from happening but the ship came in at an angle and missed them
This link says local police were notified a few minutes before and were already in the process of shutting down traffic when the collapse happened. Probably saved quite a few lives.Quote:
Originally Posted by From_the_NEK
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Impressive response time if that is true!Quote:
Originally Posted by Harry
Haven't you seen the Wire?Quote:
Originally Posted by From_the_NEK
PO LEECE can clear a corner in 5 minutes.
Sheeeeeeit
So it's a continuous truss bridge. Same design as the bridge that fell a few years ago. They go down like a house of cards.
I was in Portland when the Julie N hit the bridge. What a mess.Quote:
Originally Posted by cat in january
Im surprised they don't require a ship assist all the way to the birth.Quote:
Originally Posted by ötzi
That may change....Quote:
Originally Posted by halliday
it didnt look at all like a tough maneuver to get out of port
unless of course the ship lost power
I wonder if more ports will require the use of tugs ?
Different perspective. Wonder how long to clear and then reconstruct the bridge? Also if the towers have been structurally compromised?
Attachment 492044
Anyone know if there are protocols in place where if vehicle traffic is moving very slow or at a standstill so the bridge essentially has become a parking lot that they hold off ships passing under until vehicle traffic is flowing again?
I’ve driven over both the old and new bridges there a few dozen times visiting CHS. That old one was seriously a white knuckle experience that often required a changed of underpants upon crossing to the other side.Quote:
Originally Posted by BmillsSkier
You ain't kidding. Extra fun was when they were building the Ravenel and traffic into Mt. Pleasant would get so backed up you got to sit on that rickety-ass bridge for 45 min+ just waiting to crawl your way off. It was very much like being on a cheap carnival ride with how much that thing swayed side to side with nothing but thin metal between you and the abyss.Quote:
Originally Posted by present tense
Marine traffic always has the right of way. Looked for a direct response to the question involving fixed bridges, but since the below uses draw/moveable bridges in the example I have to assume the same would hold true with a fixed bridge:Quote:
Originally Posted by fomofo
https://www.seattletimes.com/seattle...-right-of-way/Quote:
Q:
It doesn’t seem quite right to Dave Hendricks, of Gig Harbor, Pierce County, that motorists should be so frequently held up by bridge openings for marine traffic.
“I drive into the University District sometimes three times a day, and am amazed at how many times I get caught by a bridge opening,” he said. “Sometimes I get caught [at the Montlake Bridge] going both into the district and when I come back out” a short time later. Often, he said, it’s because of rather small boats that just happen to have extremely tall radio antennae or masts. “I can lose 30 to 40 minutes due to one of these openings.”
Hendricks thinks boaters should be made to wait until several need passage before bridges are opened and traffic disrupted.
A:
Any vessel can call for a bridge opening any time, night or day. Federal law gives marine traffic the right-of-way on the Lake Washington Ship Canal and most navigable waterways. And, the operation of movable bridges on navigable waterways is regulated by the Coast Guard, which requires that bridges open for all vessels that request an opening.
That means bridge tenders lack the power to force boaters to group together before being allowed passage. And, says state Department of Transportation spokeswoman Jamie Holter, establishing a set time to open the bridge for marine traffic is not an option. But some bridges do have some “closed periods” during peak commute times, and those are usually posted.
“Bridge tenders do try and open the bridge as safely and in the most timely manner possible,” Holter said.
It was going out, not coming in.Quote:
Originally Posted by halliday
I can’t speak to the reconstruction phase, maggot Telee would be the person to ask about that, but as far as clearing the wreckage out of the way to reopen shipping that should be very straightforward.Quote:
Originally Posted by fomofo
Only two issues are the ship and the bridge. Ship is easy, it’s still afloat so just tow it out of there. A far as the bridge wreckage, the Navy has special teams called Harbor Clearance Units that train for exactly this sort of scenario. If this was a wartime situation, I bet they could clear it enough to allow shipping within 24 hours. But we are not at war, and other considerations such as SAR take precedence. Having said that, I would be surprised if shipping is not resumed in 2-3 weeks.
*basing this on my time in the Navy, where one of our war game’s involved a Soviet ballistic missile collapsing the Coronado bridge in San Diego.
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I have an experience to share, I was on the Bay Bridge in Oakland during the Loma Prieta earthquake. Fucking insane. I got back to my apartment after about 5 hours, you could see daylight through cracks in the walls. We had 1/2 an hour to grab any valuables and GTFO.Quote:
Originally Posted by present tense
And that’s when I went back to school to finish.
Maybe they can make another run of T-shirts like they did in West Seattle in 1978
"where were you when the ship hit the span"
https://www.king5.com/article/entert...1-9d362061837e
Basic back of the envelope high school level physics estimating how much force was exerted on the bridge or for that matter the amount force to stop the ship say from dropping the anchor:
Momentum is "mass in motion." Momentum = mass • velocity or p = m • v
Convert to metric: 100,000 metric ton ship = 100,000,000 kg, 7 knots = 3.60111 m/s
p = 360,111,000 kg•m/s which shows how important mass and velocity are together
Roughly, it looks there's about 2 seconds of elapsed time between impact and collapse:
Force = p / t = 180,055,500 N newton or 40,478,087 lbf pound-force
The amount of force involved explains why the bridge collapses so quickly even though at first it looks the ship barely bumps it—counterintuitive how much energy is involved with something moving so slowly. The ship would also have less rudder control at slower speeds, and possibly no rudder control at all if the crew managed to reverse prop thrust.
my dad had that shirt, we lived in alki, dad worked at king street station. my ol' man could really bitch about those old bridges and the shit show afterQuote:
Originally Posted by k2skier112
I was in the middle of the Annapurna circuit when some dude I had met somewhere says Did you hear about San Francisco?? I thought he was going to tell me yet another tired joke , but he goes on to tell me that the big earthquake and that the Golden Gate Bridge had collapsed and 30k people were dead. I didn’t get the real story until I got back to Katmandú and checked in w the embassy 2 weeks later. The telephone game is realQuote:
Originally Posted by rideit
Fuckin hell ! What a complete loser !!
Could you be any more stupid ?
https://twitter.com/GrantCardone/sta...75756784505129
Yes apparently you can:Quote:
Originally Posted by bad dancer
https://uploads.tapatalk-cdn.com/202...11025e9ecc.jpg
Usually commercial harbors that handle large vessel traffic have what's called traffic control to monitor the vessel traffic. You will see radar installations with antennas that look like vessel radar antennas on shore based locations. Large traffic (ships) are usually in contact with vessel traffic (ch 13 I believe) and if anything gets wonky they can communicate with shore based units like Port Authority NY/NJ or Bridge And Tunnel Authority to clear things out if needed. Usually, all arrivals and departures in places like Port Of New York, the vessels call in and out. For example a ferry leaving Pier 11 heading to Highlands, NJ will call to VT "Sea Streak Wall Street departing pier 11 with X number of passengers bound for Highlands, NJ and then they will call out went they get to the Verrazano Narrows bridge. When returning they will call in to VT at the bridge that they are entering VT area control and their destination. It's a pretty well oiled machine in some places.Quote:
Originally Posted by fomofo
“I’ve invested over $5billion in real estate and don’t understand anything about structural engineering” isn’t the flex he thinks it is.Quote:
Originally Posted by bad dancer
Some pretty great info posted in this thread - thx all!
Baltimore harbor's a busy place. Hopefullly this link works: https://www.marinetraffic.com/en/ais...39.255/zoom:12
All the vessels above where it says Patapsco River ain't goin' anywhere for a while. Put the cursor over the dots to see what's there.
There were only 2 bridges of this exact design ever made. One was the Tacoma Bridge, in this video. The other one is the Deer Isle Bridge, in Maine. That one's still in use, I've been over it dozens of times and that is one shaky motherfucker.
https://www.youtube.com/watch?v=XggxeuFDaDU
The announcer didn't seem to care much for the dog.
I know, right? The guy who's walking down must have left the dog in the car, wtf?
Nooooo the dog!
https://www.youtube.com/watch?v=gBxaGB65TB8
Were you by any chance at the Marin Fat Tire Fiesta the weekend before the quake? I was there with a friend and we stayed till Monday to get another ride in...glad we didn't stay 2 days I guessQuote:
Originally Posted by rideit
Years ago a buddy of mine was on Hatteras Island windsurfing, there was a big storm blowing in so he called in sick to sail a day in it. A barge broke off from a tugboat and knocked the bridge down and he was stuck there.
He couldn't tell work he was there because he'd already called in sick, so every day he called in sicker and sicker, by the end of the week they thought he was dying so they were surprised when he showed up the next Monday, he'd finally gotten on a ferry off the island.
https://www.latimes.com/archives/la-...440-story.html
Huh? The bridge in your video is a suspension bridge while while the bridge in Baltimore is a cantilever. That is about as far from an “exact design” as you can get. Not even close, you can’t even call them a similar design.Quote:
Originally Posted by ötzi
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Random bridge disaster, nothing to do with Baltimore except bridge fall down.
Continuous Truss for the win? I took my girlfriend out onto a Continuous Truss bridge before it opened to neck.Quote:
Originally Posted by Cisco Kid
right….because of the implicationQuote:
Originally Posted by Cisco Kid
“Ahhh there’s nowhere for me to run! What am I gonna do, say no”
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