Study On The Rolling Contact Stress Changing Mechanism Of Railway Curved Track

Railway development is a matter of national economy and people’s livelihood,railway transport plays a major role in the national economic construction,the high-speed,heavy-load and high density of modern railway transport organization mode makes the use condition of rail more hasten. Compared with the linear track,Structure characteristics and the stress distribution of the curve track is more complex,abrasion of the curve track(especially outer rail side grinding) is very serious, rail failure modes such as abrasion and fatigue damage are very frequent, with the economically significant losses, the traffic accident is most likely to have a major threat to the life safety of the passengers. According to the related research,the rail internal stress and its distribution determine the fatigue failure forms of rails, so to research the stress change rule of the curve track is of great significance.In this paper, based on the real geometry and boundary conditions, considering the rail base slope, ultra-high and sleeper elastic support, ANSYS software is adopted to establish curve track wheel/rail 3/d rolling contact model which is consistent with actual situation, using ANSYS/ls-dyna explicit dynamic analysis program for simulation of wheel/rail rolling contact. This paper establishes two curve rail(inner rail and outer rail) which length are both 2.5m, and selects two typical section of the rail, including the section in the middle of sleeper and the section on the sleeper along longitudinal direction of the rail, to analyze the changing mechanism of the rail Von mises stress. Comparing and analyzing the finite element models of wheel/rail 3/d rolling contact with different axle load(25t,30 t,35t), different wheel speed(200km/h,250km/h and 300km/h) and orbit curve radius(5000m,4000 m and 3000m),the Von mises stress distribution of inner and outer rail with different axle load, speed and track curve radius has been obtained, and analyzes the different Von mises stress distribution between inner rail and outer rail, the rolling contact stress change mechanism of curve track is obtained.In this paper, the research of rolling contact stress on curve track not only consider the rail base slope, curve super-high and rail bottom elastic support, but the dynamic simulation of the wheel/rail model is also in the way of high speed and heavy load. In this paper.The paper provides an important scientific theoretical basis for the prevention of outer rail abrasion and improve the service life of rail.