• BraveSirZaphod@kbin.social
          link
          fedilink
          arrow-up
          27
          ·
          7 months ago

          “Bump” is a galactically humble description of a collision with a container ship weighing nearly 200 million pounds.

          To illustrate this more cleanly, the momentum of a loaded Boeing 787 flying near top speed is 17,760,000 N.s. For this ship going at just 10 km/h, the momentum is about 260,600,000 N.s. In other words, the bridge would need to be able to sustain the equivalent of 14 9/11 attacks, simultaneously.

          The way to tolerate incidents like this is to add multiple points of isolated failure so that even if one point is catastrophically destroyed, only a portion of the bridge goes down while the rest remains intact. I don’t think there are many, if any, structures on the planet that can withstand that much force

          • RubberElectrons@lemmy.world
            link
            fedilink
            arrow-up
            12
            ·
            7 months ago

            This right here. You’d need a frankly ridiculous amount of solid stainless steel to build pylons for seaway protection, and that’s for low speed impacts.

            Kinetic energy increases with the square of velocity!

            I’m not a sailor it anything, but I suppose requiring tugboats for all harbor travel of shops over a gross weight might be a good thing. Makes more jobs, at least.

          • bbuez@lemmy.world
            link
            fedilink
            arrow-up
            1
            ·
            7 months ago

            Also in designing such a resilient bridge, don’t forget one of the design requirements is to allow access to a busy shipping port

        • Passerby6497@lemmy.world
          link
          fedilink
          English
          arrow-up
          9
          ·
          7 months ago

          Saying the bridge was bumped by the cargo ship is like saying someone got bumped in the head after having a brick thrown at them.

    • assassin_aragorn@lemmy.world
      link
      fedilink
      arrow-up
      2
      ·
      7 months ago

      The crazy thing is it isn’t even the bridge being shoddy. It’s terrifyingly simple physics. High mass objects moving slowly and low mass objects moving quickly are both incredibly destructive. I’m not entirely sure how you build safeguards against a collision like that. It would need military grade protection – assuming even the military has something which could withstand that.

      Think of it like this. A bridge is designed to distribute weight and force and stand up. It isn’t designed to take a hit like this.