Most bridges here do, and often when one needs to be demolished and rebuilt, the military blows it up just for practice.

Edit: Source for the sceptics

The deep demolition, which became a central element in Finnish post-war demolition tactics, and especially the development of readiness to counter surprise attacks that emerged as a threat scenario in the 1960s, received significant support immediately after the wars. The decision concerning structural demolition preparations for bridges was made on January 15, 1946. These preparations meant building charge wells, charge chambers, charge pipes, and charge hooks. Authorities responsible for constructing bridges were required to include the aforementioned structures in their plans, which significantly improved the readiness to destroy the bridges.

If it was not possible to place the charge space inside the abutment or pier, charge hooks could be embedded in the supports during the casting phase, to which the charges could then be attached.

  • ameancow@lemmy.world
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    5 days ago

    Why not tape them to the bridge too?

    Go get a baby. I guess something else that weighs similar would also work, but the awkwardness of a baby conveys the right level of fuss you would take with individual charges, and grab a roll of duct tape, then find a concrete wall of some kind and see how much tape you need to stick that baby to a rough old dirty concrete wall.

    (Do not detonate the baby.)

    • Akasazh@lemmy.world
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      4 days ago

      However, of you drill, you don’t need the volume of a baby, just a few of sticks of c4.

      Just take a look at how buildings are demolished, they drill holes. It’s the best way to destroy a building. Why would the Finns be silly and not do that. If it’s so important one could pre drill those holes, limiting time.

      • Iconoclast@feddit.ukOP
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        4 days ago

        Why would the Finns be silly and not do that.

        If it was not possible to place the charge space inside the abutment or pier, charge hooks could be embedded in the supports during the casting phase, to which the charges could then be attached.

        Source

    • Dasus@lemmy.world
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      5 days ago

      The point is that you could do that, with a roll of gorilla tape.

      The point isn’t it’s more awkward to do and takes longer, the point is that the explosive force delivered to the bridge would be the same. (Actually slightly more with a gorilla tape covered explosive as it would marginally increase the forces on the bridge compared to just hanging ones.)

      If you put an explosive inside the bridge, the force delivered to the structure is several times more. Thus it would make sense to have “pits” to out explosives into, not just hooks to hang them off of.

        • Dasus@lemmy.world
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          4 days ago

          Sure you did.

          I know, it’s annoying when someone asks for something to make sense when you’ve already decided it’s true no matter if it does or doesn’t make sense.

          “Charge PITS”, not “nails” or “hooks”.