Study on Methods of Lateral Deviation of Track for Static Inspecting in High-Speed Railway

Abstract

According to the critical factor of railway track geometric irregular, the deformations of track can be controlled. The lateral deviation is the key to determine the railway track irregularity. Currently, in the static inspected methods, the combined method of geodetic surveys and track surveying trolleys (inspecting instruments for static geometry parameter of track) is widely used in high-speed railway. Depending on some tests, the model of track irregularity in track surveying trolleys can be reconstructed by another method. According to the special features of track of high-speed railway, it is necessary to study on the accurate and effective lateral deviation algorithm which is suitable for the precise track inspection of high-speed railway. Based on some existing methods of construction layout in highway, the primary contents of this paper are: (1) reduces those methods to three algorithms, such as the Longitudinal Deviation Algorithm with Composite Simpson rule (LDACS), the Distance Function Algorithm of Newton’s method (DFAN) and Normal Perpendicular to Tangent Algorithm of Newton’s method (NPTAN), and (2) completes the algorithm steps of DFAN and NPTAN on circular curve, and proves the results of two algorithms on circular curve same, and (3) proposes the three algorithms to calculate lateral deviation and mileage of any rail detection points for inspecting the static geometric state of track in high-speed railway. Depending on some simulation data, the experimental results are: (1) the calculations of DFAN, NPTAN and LDACS, in which the number of subintervals of equal greater than or equal to five, meet the accuracy of the precise track detection of high-speed railway, and (2) the difference mileage and lateral deviation between DFAN and NPTAN are less than 0.001 mm, and (3) the efficiency of those algorithms is very considerable and the efficiency of DFAN is basically the same with NPTAN and higher than LDACS, and (4) the longer the transition curve is, the lower the efficiency and accuracy of DFAN and NPTAN are. The bigger the radius is, the higher the accuracy of LDACS is. According to the measurement data of the Chengdu Dujiangyan Railway Line (Cheng Guan Line), the above mentioned results of (1) and (2) can be proved correctly.