Comparison between upgraded high speed railway lines and newly built high speed railway lines

Transportation became more important for human by reason of developments in world in the late 20th century and 21st century such as; technological progress, increase of transportation opportunities for people, growth of trading volume and concentration of pruduction in certain places in worldwide. Countries make investments on railways as a solution of increasing trade goods quantity and increasing number of passenger transport. Railways' advantages was became more distinguished after developed high-speed technology. Highways have the biggest share among the transportation systems. Important reasons of that are enable people to door-to-door transport opportunities, being individual, being comfortable and less travel time for short distances. In consequence of common usage of highways, some problems shown up such as; parking, traffic density, pollution, high accident rate, longer travel time. As a result of these problems, humanity seeking a solution for overcome these problems. Making investments on railways and modernizing it is shown up as a solution for transportation problems by some countries. First modern high speed railway line in the world was started to operate in Japan in 1964. After high-speed technology became succesful in Japan, France started to invest high-speed technology and became the second country that operates high-speed railway line in the world with Paris Lyon high-speed line. In 1991 Germany, in 1992 Italy and Spain, in 1997 Belgium, in 2003 England, in 2004 South Korea, in 2007 Taiwan, in 2008 China, in 2009 Netherlands and Turkey made invesments on high-speed railways after the success of Japanese and French operations. After the idea of nationalized railway was been abandoned, countries start to entegrate their nationalized railway network in Europe. Nowadays, there are nearly 42,000 km high-speed railway lines in worldwide. Most of these lines about 27,000 km high-speed lines was built in China. Although China started to operate high speed line lately (first opened in 2008), they built more than high-speed line length that opareted in 2008 in worldwide. Transportations is became more important for China due to Chinese land area, high population, high capacity of production and distributing products to all world. High-speed railway is a solution for Chinese transpotation problems. The second country owned the longest high-speed railway line is Japan with 3,041 km lines and the third country is Spain with 2,938 km lines. 15,000 km high-speed railway lines is under construction in worldwide. Railway infrastructure is growing rapidly in world and China is leading these days. 10,700 km high-speed lines is under construction in China. Second country, which has the longest high-speed railway length under construction, is Turkey with 1,400 km lines. As a result of the lack of railway investments and highway preferred transportation policy between 1950 and 2000, railway sector could not improve in Turkey and railway infrastructure and operating speeds are limited. Turkey become a part of the new silkroad, which will build as railway, project thanks to its location. As a candidate country for European Union, Turkey was planned its railway network with considering entegration to Trans-European Transport Network. In TINA report, European Union's suggestion is building a main line form Edirne to Kars for connection between Europe, Asia, and link main port cities to this main line. Turkey started to operate its first high speed railway line between Ankara and Istanbul. While Turkey is updating its convantionel lines and modernizing them, they are also planning to link the strategical areas such as Ankara-Sivas and Ankara-İzmir. High-speed railways defined in regulations as;  Specially built high-speed lines equipped for speeds generally equal or greater than 250 km/h,  Specially upgraded high-speed lines equipped for speeds of the order of 200 km/h,  Specially upgraded high-speed lines which have special features as a result of topographical relief or town-planning constraints, on which the speed must be adapted to each case. For safety and comfortable transportation, railway lines should have some geometrical requirements such as;  Gradient,  Radius of horizontal curve,  Raidus of vertical curve,  Cant,  Cant deficiency,  Cant excess,  Length of transition curves,  Rate of chance of cant as a function of time,  Track gauge,  Distance between track centers. Calculation of geometric specifications of railway lines is indepented from building types. Mathematical formulas depends on maximum operating speeds, curvature radii, cant, acceleration etc. but geometric specifications have different limitations for each building types in guides. Recommended limits are usually same for each building type but maximum or minimum limits are more tolerant for newly built high-speed railway lines. The major difference of building types is construction costs. Although upgraded high-speed railway lines are usually more cost-effective than newly built lines, newly built high-speed lines perform better. As a result of railway construction costs and being long-lived investments, construction type should be choosen carefully by considering benefit cost ratio. In the light of these informations, a comparison was made between upgraded high-speed lines and newly built high-speed lines based on geometrical specification differences in this thesis study.