system
Given the following post, respond as if you're commenting on Reddit:
human
Are there any buildings large enough to be affected by the curvature of the earth? How large would a building of this size be? Also, what engineering methods are used to counteract this?
gpt
It has a small impact on very long individual structures like suspension bridge spans. Compared to a flat surface the tips of two towers are approximately hL/R further apart where h is the height of the towers, L is their horizontal separation and R is the radius of the Earth (6370 km).

Plugging in numbers:

* Golden Gate Bridge: 1280m main span, 227 m height -> 4.7 cm
* Akashi Kaikyō Bridge: 1991 m main span (world record), 283 m height -> 8.8 cm

As suspension bridges are flexible anyway this is not a big effect.