The Research Of Small Radius Curves CWR’s Detection And Maintenance Technologies

This paper Combines with field investigation in the small radius curve CWR,analyzes the actual process and the occurrence of rule about track swelling, analyzes the advantages and disadvantages of laying continuous welded rail on small radius curves,through the point of view about the mechanical stability and economic effect expounds the laying continuous welded rail.Through the small radius curve in the nanning railway section seamless line the observed data of the lateral ballast resistance and resistance of fastener has carried on the analysis of mathematical statistics, we concluded that the corresponding fitting formula. By using the equal wavelength model and unequal wavelength model of small radius curve CWR on stability is checked, according to the Knowledge of seamless line, combined with the Railway line project example, calculation of the CWR’s temperature when the section of the most lower temperature rise or minimum temperature, by the formula of the stress-free temperature. In addition, the combination of the local desert climate, the formula for calculating the correction value, according to the rail temperature measurement and temperature difference, the value proposed to take4.1℃, more in line with the climatic conditions of the paragraph, in the circumstances to ensure the strength of the rail to improve the stability of CWR.According to the design optimization of the Stress-free temperature, we concluded that the corresponding fitting formula.The two kinds of model calculation results the causes for the differences are analyzed from three aspects,The safe model is modified, the modified model in the same vector with wavelength ranging model are compared. From a mechanical point of view, the model which closed to the actual field was established.By using the finite element method to solve the instability problem of the small radius curve buckling under temperature forces of CWR. A track-frame model has been developed,which includes Establishing the track frame model including rails, fastener, sleepers and ballast resistance,and the finite element program has been exploited using numerical formulation.The influence of cross force was also considered in this model.The dependence of the CWR displacement on temperature figures in different work conditions were arrived,and the result was compared with the result of universal formulation. The changes and characteristics caused by temperature stress by analyzing the changes of different factors and lateral displacement, to judge whether the stability of CWR and provide a theoretical basis for the maintenance department.Analysis results show that, finite element on the stability of CWR is feasible and effective; finite element method to calculate the different conditions of track structure from the lateral displacement of locked rail temperature until the failure of the whole process.Compared with the universal formulation, the method considers the various complex conditions, can more accurately reflect the rail transverse deformation trend, which is convenient for field use.In this paper, with the establishment of a scientific testing technology of small radius curve on the common diseases of seamless line has carried on the detailed investigation, according to the characteristics of the small radius curve seamless line, summarized a set of practical effect, easy to operation maintenance technology solutions, the routine maintenance work for the public works department concept of advice and support.