Mapping Law of CRTS Ⅱ Type Slab Ballastless Track Static Deformation Due to Subgrade Horizontal Deformation

Abstract

Objective Aiming at the insufficient control indexes for high-speed railway subgrade horizontal deformation currently, it is necessary to study the influence law and limit values of ballastless track subgrade horizontal deformation. Method Using finite element method, the structural stress, deformation, and track irregularity of CRTS (China railway track system) II type ballastless track are calculated under horizontal deformation conditions of cosine-shaped subgrade with different wavelengths and amplitudes. Referring to the allowable tolerance values for track geometric dimensions and the allowable tensile stress values of ballastless track structure, the transmission law and limit values of subgrade cosine-shaped horizontal deformation are studied. Result & Conclusion The horizontal deformation of ballastless track structures such as rail, track slab, mortar layer and supporting layer shows significant response characteristics to cosine-shaped horizontal deformation of high-speed railway subgrade. When the wavelength and amplitude of horizontal deformation are 20 m and 10 mm respectively, the influence of subgrade cosine-shaped horizontal deformation on track alignment irregularity is the greatest, followed by the influence on track horizontal irregularity, while the influence on gauge and vertical irregularity indicators can be ignored. When the amplitude of horizontal deformation is 20 mm, as its wavelength increases, the maximum value of rail horizontal deformation increases, while the track irregularity, track slab and supporting layer tensile stresses first increase and then decrease. The limit value of subgrade cosine-shaped horizontal deformation amplitude increases with the increase of horizontal deformation wavelength, and the two satisfy a quadratic function relationship.

Keywords

• high-speed railway subgrade
• ballastless track
• horizontal deformation