• theroastedtoaster@lemmy.world
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    3 个月前

    It might be some sort of survey benchmark. If there’s one on each end of the bridge, it could be for measuring alignment of the movable section against the stationary section

    • Chapelgentry@lemmynsfw.com
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      3 个月前

      Sounds about right. I have seen similar markers in California to measure fault line movement on an annual basis, as well as several in Yellowstone for roughly similar reasons. Seems like this is a survey marker to measure distance or alignment.