Interesting: How high can a building be built? Theoretically 20,000 meters, but in reality it is difficult to exceed 1,000 meters

As of 2021, 11 of the world's 20 tallest skyscrapers are located in China. While we feel proud, a question has also caused us to think, that is, how high can a building be built?

At present, the tallest skyscraper in China is the Shanghai Tower, which has 118 floors and a total height of 632 meters. Looking at the world, the tallest building is the Burj Khalifa in Dubai, which has 162 floors and is 828 meters high. These skyscrapers look very spectacular on the ground, but from the data, they still do not exceed the thousand-meter mark. Why is this? Is it that human technology is not yet able to build taller buildings?

Everything has a limit, and the height of a building is no exception.

Who is the best architect on Earth? Of course it is the Earth itself, and the mountains are the skyscrapers built by this architect. What is the highest mountain on Earth? Everyone knows that it is the highest peak in the Himalayas, Mount Everest, and its height is 8,848 meters. This is much higher than the skyscrapers built by humans, but it still does not break the 10,000-meter mark. It is not a coincidence that there are no mountains on Earth that exceed 10,000 meters, but there are inevitable reasons. The height of a mountain on a planet is closely related to one factor, that is gravity.

Because of gravity, the higher the mountain, the greater the mass, and therefore the greater the pressure the entire bottom of the mountain needs to withstand. Once the pressure is too great for the base to withstand, the mountain will collapse.

From this we can see that the smaller the gravity on a planet, the greater the theoretical height of the mountain will be. We can see this just by looking at our neighbor Mars. The gravity of Mars is about one-third of that of the Earth, so there are many mountains on Mars that are over 10,000 meters high. One of the more famous ones is the Olympus volcano, which is more than 21,000 meters high.

So what is the theoretical height of mountains on Earth?

Scientists calculated a data, which is 20,560 meters. However, this data is only theoretical, because the height of the mountain is not only affected by gravity, but also closely related to the surrounding environment. For example, on a planet with a dense atmosphere like the Earth, wind, rain, external erosion, and the internal movement of the Earth itself will have an adverse effect on the height of the mountain. Taking all these factors into account, it is very difficult to exceed 10,000 meters. It is difficult for naturally built mountains to exceed 10,000 meters in height. On the other hand, with current technology, it is very difficult for humans to build buildings over 1,000 meters.

A key factor preventing man-made buildings from breaking the one-kilometer mark is structural strength.

Similar to mountains, the higher a building is, the greater the pressure it has to bear at the bottom, and the higher the structural strength required. With the current level of human technology, it is difficult to support the emergence of a thousand-meter building. In addition, whether it is a mountain built by nature or a building built by humans, they all have a common feature, that is, they are wide at the bottom and narrow at the top. This is also to share the pressure. If the width is the same at the top and bottom, the bottom would have collapsed due to excessive pressure. This means that the higher the building is, the larger the base.

In other words, if you want to build a 10,000-meter-high building, it is not enough to just stack up 10,000-meter-high buildings. Instead, you need thousands of thousand-meter-high buildings. Not only does it occupy a very large area, but the cost is also unbearable.

Furthermore, the taller the building is, the more unstable it is. In order to prevent the building from collapsing due to excessive shaking, the mass of the wind damper on the top must also be increased accordingly. In theory, the mass of the wind damper should be at least one percent of the building to be effective. Taking the Shanghai Tower as an example, the mass of the wind damper on the top of it reaches 1,000 tons. If the building is further raised and the mass is further increased, the mass of the wind damper must also be increased, which is also a technical problem. So, in theory, buildings on Earth can reach more than 20,000 meters, but in reality, it is difficult for humans to build a kilometer-long building. Even the architect, nature, is powerless in the face of a 10,000-meter building.