What is a high-speed train: Just 63 years ago, in l961, I am a student at the boarding Railway Vocational High School in Ankara. In the professional "Railway" magazine, there are illustrated news about the high-speed trains in Japan:
”500 km from Tokyo to Osaka. The high-speed trains traveled this distance in two hours without stopping. “Such a high-speed train technology in our country could not have been imagined. At that time, steam trains were running on our railways across our country, even among the important centers. The highest speed they can make is 90 km per hour. was. There were motor trains, trains operating with diesel locomotives were still in the process of meeting our country's technology. Steam trains continued to exist in our country until the mid-1980s. After this stage, trains with diesel locomotives and trains with electric locomotives among important centers such as Ankara - Istanbul continued to be the most advanced technology for our country. Even the average speed of express trains from passenger trains is 50 km per hour. until the beginning of the 2000s.
In the railway literature, trains are divided into three groups:
- Passenger trains
- Cargo trains
- Business trains
The last 8-10 is divided into three categories in terms of speed in the modern railway literature.
- REGIONAL TRAIN for trains up to 160 km / h.
- Its speed per hour is 160 - 250 km. FAST TRAIN to trains
- The speed on the hour is 250 km. and more trains are called HIGH SPEED TRAIN [YHT].
The technical specifications that I will describe hereafter relate to the standards of High Speed Train technology.
The political power that changed in the first years of the new millennium recalled the importance of Railway transportation, which it neglected and pushed aside in the country's economy for 50 - 60 years. Thus, he quickly initiated the work of renovating neglected maintenance and very worn parts of conventional lines, besides, he pressed the button to bring the high-speed train technology to our country. As it is known, construction started between Ankara and Eskişehir, that is, in the most suitable environment of our country as land condition. It was commissioned in 5, 2007 years later. Then the Ankara - Konya line was built and put into service. As it is known now, Eskişehir - Istanbul High Speed Train Construction, which has been under construction for 5 years, has been completed. Test drives continue. It will be put into service soon.
Our people loved High Speed Train technology, which is a great competitor and alternative to airline transportation.
As expected, High Speed technology is a very advanced technology. The road infrastructure and superstructure is a different technology with the high standards of the towing and towing vehicles that will travel on this road. The slightest negligence in the maintenance and control of roads and vehicles - due to the high speed - can cause major and irrecoverable accidents and losses. However, the possibility of negligence and error can be prevented to a great extent as a result of daily and strict control, maintenance and intervention in the system. Care is required in the selection of the personnel involved. A safe working environment can be provided with a very good education and supervision. Fortunately, there have been no major mistakes and accidents in Business Administration so far. The system has sat down. In addition, it brought the western style systemic and meticulous working environment to our country and made it a tradition.
As it is known, as in every construction, infrastructure and superstructure are in question. Within the scope of the infrastructure, constructions such as the tunnel [overcoming the water obstacle] viaduct [overcoming large and long pits] bridge [overcoming the water barrier] viaduct [overcoming big and long pits] tunnel [overpassing the mountains and hills] underpass and overpass bridges are included. The dynamic high speed vehicles that will pass over these constructions must have the quality standard to carry the dynamic load. This is very costly compared to infrastructure construction in conventional lines. Its standards have been determined by international agreements.
The superstructure is formed by laying concrete traverses manufactured in a special standard on the “ballast”, which consists of pieces of broken stones of certain quality and standards laid on the platform, and by connecting a pair of rails made of certain standards and quality on these traverses. High Speed Train rails are in wider cross-section and weight compared to conventional lines.
In addition, high speed train arrays are also included in the superstructure. As you can guess, it is necessary to have standard and quality, such as the powerful engine and the vehicle axles are not burning at high speed.
"Superstructure geometry" is also very important in YHT road technology. Let's briefly describe the relevant basic terms to understand this topic:
When we consider the road in the vertical direction; If there is no elevation [height] difference between the two specific points of the road, such a road is called a straight road, a slope or a sloping road if there is a height difference between the two points. In YHT standard, the road should be at zero slope or very close to zero slope, very little slope. Because inclined roads, ramps, are formations that limit speed.
When we consider in the horizontal direction, there are two different road types such as the right path and the curved path. Curved paths radius is the arc of a particular circle. Curved roads are called - curves - in road technology. The greater the radius of the curves, the faster the vehicles on it. As the radius gets smaller, it limits the speed. For example, if the curvature radius is 300 meters in a conventional line, the maximum speed of the vehicles is 70 km / h. When this speed is exceeded, vehicles can be swung out of the center and tip over. Because, according to the physics rule, the objects rotating circularly are pushed out of the center of the circle with the effect of - centrifugal force - and are thrown as a result. For this reason, the curves in YHT standard should not be at all or they should be in very large radii such as 3500-5000 meters at least close to the "right way" feature.
These superstructure geometry standards, ie zero and zero inclined roads, very large radius curves, also affect the infrastructure standards and YHT road construction of large, high, long and wide bridges, tunnels, viaducts have to be built. As a result, the cost of road construction is very high. It is very difficult to realize these standards in very rough terrain.