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Tangentially related. What caused cable-stayed bridges to so increase in prominence over the past few decades? I did some reading and they've become a popular choice for bridges and have advantages (e.g. not requiring really solid anchoring for the ends of the cable) but I haven't run across a good explanation about what made the design popular where it hadn't been before.

Does the increased use of pre-stressed concrete have anything to do with it?

T Y Lin discusses some neat aspects of bridge design that touch on this in his oral memoirs. [1]

IIRC, cable-stayed bridges have the advantage of being able to be cantilevered from the tower out during construction. Their disadvantage of compressive load on the deck goes nicely with prestressed concrete's strength.

The whole memoir is really good.

> Lin: This was all concrete. Except the cables. See, cable bridges are really prestressed concrete. To tighten the cables against the concrete, but put the cables outside; for ordinary beam, the cables are inside. When the bridge gets too long it is cheaper to put cables outside, so it s really a type of prestressed concrete bridge. They call it cable-stayed bridge. It's post-tensioned concrete. So, okay.

[1] https://archive.org/details/fatherprestressed00tylirich

Then the underlying reason would be price. Prestressed concrete can't compete with steel in strenght/weight ratio. But the strenght/price ratio makes it good choise for some budget designs.

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