On April 29, according to Science China, as soon as the annual holiday opens, the train ticket is almost secondary. Especially on May Day this year, due to the unprecedented enthusiasm of tourists, the difficulty of purchasing tickets for some popular routes is not lower than that of the Spring Festival. Many netizens "complained" that the 12306 APP was "waiting for invoicing". #12306 seconds did not # rushed to the hot search, causing widespread attention.
Some people can't help but have such questions:
Why is it that the vast majority of trains on general-speed railways and high-speed railways are in the daytime, but there are so few trains at night? Can't we add some trains at night to relieve the pressure on transportation?
In fact, there is a similar question, that is, why does the subway in the city stop operating at 11 or 2 o'clock in the evening?
A Fuxing train departed the Tianjin EMU. Image source: China State Railway Group Co., Ltd
To answer this question, we have to mention a more professional concept - sunroof. The "sunroof" here is not the window on the top of a car or building as we understand it, but a proprietary concept of rail transit.
According to the description of "skylight" in Chapter 3 of the Measures for the Safety Management of Railway Business Line Construction, we can know the following definitions:
"Skylight refers to the time reserved for construction and maintenance operations without paving the train running line or adjusting or reducing the train running line in the train timetable, and is divided into construction skylight and maintenance skylight according to use. ”
Maintenance or overhaul is essential and important for any type of transport.
In this way, it is clear that a very important reason is that the necessary maintenance and construction of the line is required during the night, which can take up a certain amount of time.
The new operating chart will be implemented on December 30, 2019. Image source: CCTV News
For example, in a certain position of the line, due to the design change, several signals or several sets of turnouts are added, and the corresponding interlocking logic of the station should be rewritten, and then the corresponding application software upgrade should be carried out, which is obviously a change in line conditions.
For example, if a line is transferred from a railway bureau to another railway bureau for jurisdiction, the dispatching management of the line should be reconnected by the new dispatching and command center, which obviously needs to be fed back to the center's operation diagram and large screen changes, and correspondingly, the centralized dispatching control system (CTC, Centralized Traffic Control System) may need to be transformed. Obviously, this kind of work is not allowed to be operated during the daytime train operation. The specific construction will have to wait until the "construction skylight" time period mentioned above, and this time is generally at night.
Taking high-speed rail as an example, the regulations require that in principle, the skylight time should not be less than 240 minutes, but in fact, including the preparation before the construction entry, the reservation of construction emergency time, and the cleaning and restoration of the site after construction, the default skylight time will generally be between 00:00 and 06:00 in the morning. That's why it's rare to see a train with the G/D/C prefix departing during this time period.
But fortunately, there are many railway lines, and there is generally not only one transportation line between the two cities, so we also have the opportunity to take the "bullet train sleeper" such as the Beijing-Shanghai D7. In a sense, it satisfies some passengers who often travel on business but struggle to catch red-eye flights.
Of course, in addition to the major line maintenance issues that limit the nighttime operation of rail transit, passenger traffic is also a consideration.
As we all know, whether it is the subway or the railway, as the public infrastructure of the city, it has a certain nature of public welfare service in it. This is one of the main reasons why China's high-speed rail/subway is still being built at a loss.
Although rail transit has the nature of public welfare, but it also carries a lot of workers who have paid for it, blindly relying on state subsidies is obviously unrealistic, or to create profits on the basis of completing basic tasks. However, with fewer passengers at night and less dense travel, it is understandable that there will be a lot of resource loss to make the number of railway trains as much as during the day.
In addition, as we all know, the rail transit industry is a typical "three-shift" work system for operation staff. While nighttime equipment is mostly "inefficient" to operate, on-duty personnel are essential. The night is a time for people to rest, and their mental state cannot be compared with that of the day, and if a large number of trains are driven at night, it will also cause greater pressure on the staff themselves.
[Source: Popular Science China]
Disclaimer: The copyright of this article belongs to the original author, if there is a source error or infringement of your legitimate rights and interests, you can contact us by email, we will deal with it in a timely manner. E-mail address: [email protected]