Someone once calculated a simple question: the total length of the Beijing Shanghai high-speed railway is 1318 kilometers. The maximum speed of the high-speed direct train from Shanghai Hongqiao Station to Beijing south station is 300 km / h, which can be reached in 4 hours and 24 minutes. But what is puzzling is that in fact, even the fastest train took almost half an hour to arrive. So, how does this time come out?
This seemingly very simple problem is closely related to the complexity of railway train operation. Railway lines across the country crisscross, forming a huge "chessboard", and trains are like pieces on the chessboard. There are certain rules for each chess piece, and certain rules must be followed for each train. When the train starts, stops and how fast it should be are arranged by the dispatcher, not by the train driver himself.
Obviously, the operation arrangement of railway trains is a very complex work. In order to ensure the punctuality and safety of trains, it is necessary to have a huge organization to compile and command the whole process of train operation, which is usually called railway traffic dispatching. This kind of dispatching work was implemented by regions and layers from the then Ministry of Railways to the Railway Bureau and then to the station. The control of train speed is only part of it. Now, let's take a look at the mystery.
First of all, how fast the high-speed train can run depends on the condition of the railway line. It's like driving the same car on the highway or on the gravel road in the mountains. Its speed is completely different. The distance of high-speed railway is long, and there are both straight and curve in the line. When the train enters the curve, in order to prevent the train from derailing or overturning, the train needs to reduce the speed. In the process of traveling, the train may pass through bridges or tunnels. At this time, its line structure and environment will change, and the train will slow down. Even if you drive on a straight road, you will drive at different speeds due to different conditions of different foundations. It can be seen that these environmental factors on the line determine that the train cannot run at the highest speed from beginning to end.
In fact, before the high-speed train leaves, people will record the speed data of different sections of the whole journey in the readable and writable electronic chip of the monitoring device. If the train is speeding, the equipment will remind the driver and automatically take countermeasures. Secondly, some sections of the line often need to be replaced or repaired temporarily, and the train should also slow down when passing through these places. Once the line ahead breaks down suddenly or the train ahead is delayed, the train has to slow down and sometimes can only stop and wait.
On a high-speed railway line, it is often necessary to run multiple high-speed railway trains with different speeds, stopping at different stations and arriving at different terminals, so as to improve the utilization rate of the line and meet the needs of different passengers. Therefore, it is necessary to scientifically arrange the running speed of all trains. In addition, it is inevitable that trains avoid intersection, stop and control speed, which is also one of the reasons why high-speed railway trains can not travel fast all the way. No wonder the real-time speed of the train is always changing on the display screen above both ends of the high-speed train carriage. In fact, this change in speed occurs not only on high-speed trains, but also on ordinary trains.