The Sky's the Limit
Is There a Limit to How Tall Buildings Can Get?
Ask a building professional or skyscraper expert and they’ll tell you there are many limitations that stop towers from rising ever-higher. Materials, physical human comfort, elevator technology and, most importantly, money all play a role in determining how tall a building can or can’t go.
But surely there must be some physical limitations that would prevent a building from going up too high. We couldn’t, for example, build a building that reached the moon because, in scientific terms, moon hit building and building go boom. But could there be a building with a penthouse in space, beyond earth’s atmosphere? Or a 100-mile tall building? Or even a 1-mile building?
1) Water flowing up. A single pipe a mile high would have base pressure of 160,934 grams/cm^2 or 2300, psi plus more for friction losses and delivery pressure. A rupture would be energetic and messy. This is negotiable as vertically periodic pumped sumps.
2) Sewage flowing down. Pipe internal erosion will be interesting. If it is a solid column of fluid the base pressure problem is much worse for downward accelerated flow. There is no off switch for momentum. If it is free fall in air there is pneumatic compression (101.325 J/liter-atm). Either way, clogging is a potential bomb (continuous injection of detergent? In situ primary treatment?). Parallel waste pipes for successively lower stories?
3) Terrorism: Simultaneous flush atop. Flushed balloons containing freshly mixed polyurethane foam to inflate and occlude.
4) Upon what will the building stand? Manhattan bedrock is thick granite gneiss and garnet schist. Good stuff! A softer, thinner base rock will depress over time – especially if it is threaded with aquifers that can be squeezed out.