Study On Riding Comfortablity Evaluating Methods And The Application To Selection Of Line Parameters Of High Speed Railway

China has a large population and territory, the best approach to solve large-scale population migration is High-speed railway. As is planned, up to 2020, the mileage of China's High-speed railway will exceed 180000 km, half of the mileage of the world's total at least.High speed is a very important direction for China railway's modernization. High speed railway should be developed, at the same time, make sure that the operation quality should not be decreased as the running speed is increasing. It is an important subject for us to increase the riding comfortablity through reasonable settings for line parameters.This paper discusses the theories of riding comfortablity, analyses the main factors of riding comfortablity, and introduces the mainstream riding comfortablity calculating method in the world, proves that UIC513 method is suitable for China.Also the Sperling method program and UIC513 method program are compiled, using MATLAB. Based on these, the correlation of Sperling method, UIC513 method and ISO2631 method is deduced.At last this paper summarizes research methods of main line parameters of High-speed railway, such as the minimum radius of horizontal curves, length and alignment of transition curves. Based on these, this paper simulates the acceleration data by using a dynamic model of Vehicle-Track Coupling System, calculates the comfortablity indexes in different conditions, and finally makes a dynamic analysis of related results in the term of riding comfortablity.