• Flying Squid@lemmy.worldOPM
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      8 months ago

      People are crazy. People claim planes didn’t hit the twin towers.

      And in both cases, there are the “the planes/boat didn’t do it alone” people.

      • SpaceCowboy@lemmy.ca
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        8 months ago

        Yeah it was over 100,000 tons going at around 8 knots. Not exactly high speed, but think of the momentum of something that’s 100,000 tons.

    • exanime@lemmy.today
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      8 months ago

      Oh yes… Right here on Lemmy some person said they should just drop some heavy concrete blocks near the bridge bases to stop the ship …

        • exanime@lemmy.today
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          8 months ago

          Nope, I did argue that it was not as easy as someone was claiming (dropping “heavy blocks”)

          Only one person replied with a link, but their very link said no protection would stop this specific accident

          PS: you should also read your links. They are not super detailed in that wiki article but nothing there detour, much less stop, the ship that knocked down the Baltimore bridge

        • 【J】【u】【s】【t】【Z】@lemmy.world
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          8 months ago

          Seems like those are to deflect canoes and pontoon boats, maybe a small pleasure craft or fishing boat. Not a fully loaded cargo ship. I don’t see anything that could have prevented this short of using tug boats to navigate the channel. The boat lost power and drifted into the bridge. Nothing short of a land mass was going to stop it once it lost power.

          • Deceptichum@sh.itjust.works
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            8 months ago

            No it does not seem like that.

            These systems are designed to protect bridges before a ship hits it.

            https://www.sciencemediacentre.org/expert-reaction-to-baltimore-bridge-collapse/

            Look at what the fucking engineers are all saying, it all boils down to “We would expect to see measures in place to redirect the ship because a bridge cannot survive a direct hit.”

            The bridge was built in the 70s and nobody wanted to spend the money to update the safety measures to protect from modern cargo vessels.

            • 【J】【u】【s】【t】【Z】@lemmy.world
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              8 months ago

              "From the photos I can see what appears to be a solitary dolphin-type structure on each side of the two main piers. If so these look to be inadequate to deflect anything other than small vessels. I do not know what measures were planned or installed when the bridge was opened in 1977, but the sizes and weights of cargo vessels have increased enormously to the present with the globalisation of container sea transport.”

              I see what you mean. Very cool site. Thanks for sharing. I hope the fediverse is used to marshal actual expert, similar to how this site does it, but more crowd sourced, like Wikipedia. Anyhow, seems like the bridge should have been replaced in addition to deflection devices.

            • WoahWoah@lemmy.world
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              8 months ago

              The very article you linked, from the first of the experts, states, “There was no way to protect the bridge, even if there was a warning system in place. If a ship like this collides on with any bridge it may take it down.”

              Each expert after basically says the same thing. Even with extra protections using modern technologies, a head-on collision from a boat of this size and weight would destroy almost any bridge, and there is no practical fender system to effectively deflect a ship of this size. Most suggestions are that a more modern bridge would simply have a wider channel, but a modern bridge with modern fenders and plant of dolphins would not have stopped a head-on collision like this. And a wider channel wouldn’t matter if a boat if this size still ran directly into one of the (wider spaced) direct supports.

              Other experts here note radar and sonar protections and lighting, none of which would have mattered here because the problem is the Dali lost power and navigation, which is what caused them to run directly into the bridge pylon. The pylon could have been made out of neon lights: they couldn’t turn. I don’t think you’re taking into account just how massively heavy this ship is.

              • Deceptichum@sh.itjust.works
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                8 months ago

                That says there is no way to stop a head on collision, which is true. Hence why you divert the boat before it hits the bridge structure.

                As I have already mentioned and as many of the other professionals in that site point out:

                “It is almost impossible to design a bridge pier to withstand this kind of impact. Therefore, we tend to design impact protection measures to prevent it from happening instead.

                And

                “From the photos I can see what appears to be a solitary dolphin-type structure on each side of the two main piers. If so these look to be inadequate to deflect anything other than small vessels.

                And

                I do not know the history of this bridge, but it looks like an old bridge that was designed neither for ship impact nor had any ship impact barrier to avoid the problem.

                And

                ”I do not know what the arrangements were for this bridge but major bridges over shipping lanes must have substantial protection for piers or columns. These protections are either in the form of structural protections like ‘sacrificial dolphins’, which are made of steel and embedded in the seabed to stop or divert a ship.  They can also be in the form of artificial islands; these are for very large ships and mean the ship will never reach the bridge pier itself. If piers are not protected adequately then they are vulnerable to ship collision. Clearly the protection of the piers in this instance was inadequate.

                And

                Bridges in shipping lanes are sometimes designed with strong, stout piers, or additional protective structures around the piers to prevent ships from coming into contact with the bridge structure. It doesn’t appear that the Key Bridge had either of these features

      • Liz@midwest.social
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        8 months ago

        That’s basically what a “dolphin” is and you can build them arbitrarily large. The only reason this bridge wasn’t retrofitted with adequate protection was money. As with any large-scale disaster, there are multiple failures that lead to the incident. The boat is clearly to blame, but so is the bridge protection system.

      • Bytemeister@lemmy.world
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        8 months ago

        I’ve seen videos of much smaller ships running aground, and they manage to win against the earth itself for a considerable distance before they stop. Some rebar and concrete pylons aren’t going to cut it.