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The more horizontal a building (on planet earth) is, the more years it can survive a collapse?

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The question may seem stupid but for someone with both a fear of heights and a collapse anxiety can choose renting/buying an apartment in a very horizontally wide building and a very vertically wide building (both with pretty much the same number of apartments with the same apartment sizes and commodities), an answer could be very helpful.

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You are accessing this answer with a direct link, so it's being shown above all other answers regardless of its score. You can return to the normal view.

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This is general mechanics: all objects have a center of gravity. On a square-shaped house, this center is right in the middle, at coordinates (width/2, height/2). The wider the building is in relation to the height, the closer to the ground the center of gravity gets.

A building might collapse when the center of gravity for some reason ends up outside the base of either wall, as illustrated in here. Where the blue dot is the center of gravity and the arrow is the G force of earth.

Now of course the question if/when it collapses is more complex than that, it also depends on material, weight, friction of foundation vs the ground, how large the basement is etc etc (just look at the Leaning Tower of Pisa). In modern engineering, the quality of concrete, rebars and so on likely matter much more than mechanics. And naturally, buildings in areas with lots of seismic activity like earthquakes face higher risks.

So in general, a person with a collapse anxiety should pick a building with a big width-to-height ratio, even though the chance of collapse mostly depends on quackery during construction, such as using bad concrete. And they should avoid living in an area with seismic activity (North- and South American west coasts, Central America and the Carribeans, South-East Europe and most of Southern Asia, see this map.)

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You can't go by the shape of the building alone. No matter what the shape, presumably structural engineers carefully considered how the building will support itself. Buildings are not single monolithic structures. Failure by "tipping over" is very rare.

Buildings generally fail when the right combination of individual structural elements fail. You might think that tall buildings are therefore at more risk. That is not necessarily so, since the support structures were designed for the load, and therefore are much more sturdy.

For example, you can build a simple structure with a few spindly posts holding up a flat roof that falls down in the next breeze. On the other hand, there can be 3-story structures that withstand hurricanes and earthquakes. Building codes usually require structures to withstand some level of earthquake and wind loading. Taller structures are more susceptible to these, but also designed stronger as a result.

For a building to be safe, the engineers had to do the calculations correctly, the builder had to follow the design correctly and use the proper materials, and the inspectors had to verify this. Any broken link in this chain can lead to disaster. There have certainly been cases of bad design, builders saving money by using sub-standard materials, and inspectors getting paid off to look the other way.

So how can you know any one building is safe? You don't. That's life. You are implicitly trusting in the process every time you walk into any building, cross a bridge, go under a bridge, enter a tunnel, ride an elevator, or even drive a car. There is risk in everything we do. Fortunately, we have systems in place to mitigate risk from structural failure. A building falling on you is a tiny risk in most places relative to other risk you routinely take without even thinking about it.

Of course, there are enough test cases that even with very low risk, there will be some failures. A famous example of unsafe design was the Citycorp tower in New York City. The engineer screwed up, and the building would likely have collapsed in the right wind storm. This was caught by someone looking over the design well after the building was built. The building was quietly upgraded to fix the problem. Meanwhile people in the building were taking much higher risk than they thought. In this particular case, the fix was in place before the right winds came along, and nobody got squished under tons of crumbling concrete.

As Dirty Harry would say, "Do you feel lucky? Well, do ya, punk?". In the end it's a probability game, with the shape of the building having little to do with that probability.

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