## 4 Conclusions  
This paper, considering the relative motion of stock/switch rails, establishes a wheel-rail rolling contact model, simulates the rail surface initiated RCF behavior by taking a section of switch rail with the head width 35 mm in a high-speed railway turnout called CN60-1100-1:18 and a nominal LMA wheel profile as the objects of analysis, performs a contrast analysis on the rail surface initiated RCF of turnout under different wheel-rail creep conditions and finds that the material ratcheting effect is mainly caused by the overly high tangential stress on the rail surface material under low wheel-rail creep, overly high tangential stress and normal stress on the rail material under high wheel-rail creep and overly high normal stress on the rail under pure wheel-rail spin creep. The dynamic parameters which can significantly influence turnout rail surface initiated RCF are selected according to the three-level unreplicated saturated factorial design method. The 13 dynamic parameters influencing the dynamic vehicle-turnout response are selected as the analysis factors first, then the normal wheel-rail force, longitudinal creep force, lateral creep force and contact patch area are selected as the observation parameters. The dynamic parameters influencing the rail surface initiated RCF of turnout are the train speed, train axle load, wheel-rail profile, integral vertical track stiffness and wheel-rail friction coefficient, respectively, which can be obtained according to the \(H/P/B\) statistic values. Based on a given nominal layout of ordinary turnout, axle load, wheel-rail friction coefficient, and wheel/rail profiles are selected as the parameters which could affect the performance of railway turnout significantly in the previous work. These conclusions could be corroborated by this paper. In addition, a high-speed railway turnout is used in the present work, and there are some different results, such as the integral vertical track stiffness. This paper aims to provide guidance for the simulation and prediction of rail surface initiated RCF of turnout. This RCF is caused by a long-term accumulation and the influence of changing parameters of the vehicle-turnout system. Therefore, establishing a model for simulating and predicting this fatigue through generating random samples for dynamic parameters of the vehicle-turnout system and presenting a superimposition and accumulation method for rail surface initiated RCF damage is expected for further work. In addition, with the development of computer technology and finite element theory, some complicated wheel-rail rolling contact problems have been solved by the explicit finite element method [38; 39]. Therefore, investigation of turnout rail surface initiated RCF behavior using this method is also the next step in the future works. The present work has been supported by the National Natural Science Foundation of China (51425804, 51378439, and 51608459) and Key Project of the China's High-Speed Railway United Fund (U1234201 and U1734207). [PERSON] and [PERSON] conceived and designed the idea and numerical study; [PERSON], [PERSON] and [PERSON] analyzed the data and contributed in writing the paper; [PERSON], [PERSON] and [PERSON] contributed in obtaining the funding for performing the research. The authors declare no conflict of interest. The following abbreviations are used in this manuscript:  
RCF Rolling Contact Fatigue  
3D Three Dimensional  
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