| With the popularization and application of jointless track,reducing the longitudinal displacement of rail and ensuring the stability of the track has become an important part of track research,and the rail expansion regulator plays a significant role in regulating the longitudinal displacement of rail.It is particularly important to ensure the reliability of the structure.The application of structural reliability theory mostly occurs in the reliability calculation of CWR.Referring to the basic knowledge of CWR,this paper introduces the basic knowledge of structural reliability theory and the calculation methods of common reliability,and determines the structural function that affects the rail expansion regulator.The main random variables affecting the reliability of rail expansion regulator are rail fatigue strength,temperature and wheel load.Through data statistics,the distribution form of probability density function of random variables is analyzed,and its reliability index and safety factor are calculated by equivalent normalization method.On the basis of structural reliability theory,the static index of rail expansion regulator is analyzed,and its reliability is considered from the structural line type of rail expansion regulator.The planing length corresponding to different planing line types is derived from the formula,and the influence of planing length on structural stability is analyzed According to the basic rail stress state of rail expansion regulator,the basic rail curve deformation analysis model is established,and the lateral stress of the basic rail is obtained by ANSYS analysis software,and its reliability index and safety factor are obtained by its lateral stress The influence of different linear parameters on gauge widening is calculated by using the derived formula and Matlab,and the reliability index is obtained within the calculation range.The results show that the cutting line type is preferred in the specific environment,and the cutting radius should be reduced as much as possible to reduce the cutting length;If the stress difference between the inside and outside of the basic rail in the curve section is improved,the section with larger curve radius should be selected as far as possible to ensure that the rail expansion regulator can play its role stably in the line;The reliability index is generally lower than the central safety factor,which is due to the discreteness of basic random variables and the central safety factor can not fully express the reliability;The overall reliability index of last contact curve is greater than that of single circle curve,that is,last contact curve is more stable than single circle curve.The widening of structural gauge is mainly affected by the lowering value of sharp rail;Longitudinal displacement produces gauge widening,and the maximum gauge widening value appears near the point where the sharp rail decreases,so the overall gauge widening reliability is relatively stable. |
