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Ask HN: Can skyscrapers act as pillars for suspension bridges?
You could even have a skyscraper acting as a pillar for several suspension bridges at different altitudes and directions.
Why isn't this done to handle heavy car traffic in densely packed cities?
- dylanhassinger 4y agoit would block sunlight from the street level probably would also complicate ownership & liability
- DougMerritt 4y agoI'm not that kind of engineer, but I have read that skyscrapers are largely designed to be strong about supporting the weight from levels above, but nowhere near as much to resist lateral forces beyond the wind -- and even there, high winds make the tallest skyscrapers sway and resonate, and dealing with that is one of the things they design for. (As an aside, in earthquake country, modern large expensive buildings actually rest on some kind of roller/springs/etc with dampers, so the building can move rather than break. [0]) Before the modern era, flying buttresses [1] were needed to support the then-largest buildings (churches etc). These days modern steel with rebar concrete and other techniques make those unnecessary, but I wouldn't be surprised if they would be needed even now to act as pillars for bridges, elevated freeways, etc. I may be misunderstanding something there, but it's not clear that you're going to get an answer from a skyscraper civil engineer today. [0] https://en.wikipedia.org/wiki/Seismic_base_isolation https://en.wikipedia.org/wiki/Seismic_base_isolation [1] https://en.wikipedia.org/wiki/Flying_buttress https://en.wikipedia.org/wiki/Flying_buttress
- yuppie_scum 4y agoI think drone landing pads or gondolas might be a more realistic solution for skyscraper level transit.