This thread is amazing. So many spectacular, historic photos.
Yeah! They kinda look like they can collapse anytime. But looks can be deceptive. For a strong building that will stand for a long time, the design of the building should be proper with a strong foundation. If the steel frame of the building is built in the correct manner(ie the steel columns and I beams are properly arranged and welded), the foundation of the building is strong and the materials used in the construction of the building are of high quality then I believe the building won't suffer any major problem for a sufficiently long period of time.FANTASTIC renderings, though they hardly look safe!