Why don't elevators in skyscrapers stop at every floor?

Those who are interested may find that when you go to a high-rise building, the elevators there do not all stop from bottom to top, but are set up in sections, such as different elevators stop at high, middle, and low areas, odd floors, even floors, or go directly to a certain floor. Maybe you will think, how great it would be if every elevator could go up and down at the same speed and reach any floor you want to go to?

Skyscraper Elevator

Do a simple arithmetic problem and you will understand. In a 100-story building, if the elevator stops at each floor and each stop takes 15 seconds, it takes 3,000 seconds to go up and down, which is equivalent to 50 minutes. This period of time is not short! On the other hand, a 100-story office building can accommodate at least 10,000 staff members, and the conventional passenger capacity of an elevator is 1,600 kilograms, which means it can carry up to 21 people. Taking the elevator to and from get off work requires nearly 1,000 trips each time. Moreover, people often need to use the elevator multiple times a day. In this way, the entire building is filled with elevators and there is no time to transport them. Even many people have not waited for the elevator before they get off work. Obviously, the number of elevators in high-rise buildings cannot be increased indefinitely. On the one hand, it takes up too much space, and on the other hand, it increases investment. The capacity of elevators cannot be increased indefinitely either, because the more people ride, the greater the possibility of choosing different floors, and the longer the cycle of a single elevator operation. The high speed of the elevator is necessary for high-rise sections, but it is not practical for low-rise sections, just like a high-end sports car that only runs 5 meters each time. Not only does it not show performance advantages, but the investment and maintenance costs increase exponentially. It can be seen that every elevator is equally fast and can stop at all floors. Not only does it not bring convenience, but it is time-consuming and costly.

The zoning and segmentation of elevators in skyscrapers can ensure the safe and quick evacuation of people and goods flows. Under normal circumstances, the main method of segmentation of elevators in high-rise buildings is to divide the building into several sections in height, and low-speed elevators can be used in the low-rise sections, and the elevators in the high-rise sections only stop at the high areas. This can not only reduce the number of stations that may stop, shorten the round-trip time, but also save space, equipment and investment. For example, floors that do not stop do not need to be equipped with hall doors and elevator waiting halls, and elevators in different sections can also run in the same shaft without interfering with each other, and the saved space can be used for different purposes. In order to increase the transportation capacity, elevators in skyscrapers sometimes use double-decker cars, just like double-decker buses, so that the number of passengers transported at one time is immediately doubled.

Of course, those high-rise buildings, especially super-high-rise buildings over 250 meters, often have multiple functions. Therefore, elevators should also be divided into corresponding zones according to their functions to avoid interference caused by cross-flow of people. Take the Jinmao Tower in Lujiazui, Pudong, Shanghai as an example. This skyscraper has 88 floors, is 420.5 meters high, and has a total construction area of ​​290,000 square meters. It has multiple functions such as office, accommodation, catering, exhibition, entertainment, and sightseeing. The number of people entering and leaving the building every day is about 13,000. Jinmao Tower has a total of 77 elevators, with the longest running distance being more than 300 meters. Elevators in different sections run at different speeds to achieve the highest efficiency. Relying on scientific configuration, it not only achieves the goal of fast and direct access to different areas, but also the waiting time for elevators in all areas is less than 45 seconds. Among them, in the office area on the 3rd to 50th floors, there are five groups of 26 high-speed elevators - 5 to 6 elevators are equipped for every 10 floors, which can ensure that every company employee only needs to take an elevator once to reach his office. Even during rush hour, the waiting time for the elevator does not exceed 35 seconds. On the 53rd to 87th floors, the Hyatt Hotel with 555 rooms allows guests to enter the lobby on the 54th floor directly from the ground floor, and then take the hotel's dedicated elevator to the floor where the guest rooms are located. There are also two high-speed elevators, each of which can carry 33 people at a time, and can take tourists directly from the underground floor to the sightseeing floor on the 88th floor in just 45 seconds.