| Surface damage of wheels and rails is one of the most serious problems in railway engineering. The studies on surface damage have not perfectly explained the mechanism of its initiation and growth that are effected by many factors. Based on extensive researches on the damage of wheel/rail surface, the oblique crack of rails which occurs in curve track of Guang-Shen quasi high speed passenger transport railway line is studisd in this thesis. The main purpose of the current study is to explain the formation mechanism of oblique crack and provide some effective preventive measures.The relation between wheel-rail contact force and oblique crack in rail is qualitatively analyzed. Some types of surface damage are interdependent in their initiation and growth process.Based on railway vehicle-track coupling dynamics theory, dynamics model, which is used to analyze interaction between quasi high speed train of Guang-Shen railway and curve rail, is set up. Dynamic Simulation Analysis Software (DSAS) is compiled by using Fortran90 computer language and the dynamics equations are solved by using a new and fast explicit numerical integration method. From dynamic interaction of wheel and rail obtained by DSAS, the initiation mechanism or reason of oblique crack in rails is studied in detail.Dynamic interaction of wheel-rail is studied by using DSAS software when Blue-Arrow power car, trail car, "SS8" locomotive and passenger car with "209" bogies pass through a curve with severe rail oblique crack in Guang-Shen railway, respectively. Results of the above cases are compared and analyzed. Based on these results, effect of track structure parameter and train speed on dynamic interaction of wheel and rail in curve track is discussed, and a set of synthetic and effective technology measure which eliminates or releases rail oblique crack is put forward, The results can be expected to provide theoretic basis and guidance for engineering practice.
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