|
|
|
| Research on the Stability Theory of CRTS Ⅱ Slab Ballastless Track on High-speed Railway |
| ZHANG Xiang-min1，ZHAO Lei2 |
| （1. Central South University，Changsha，Hunan 410075, China；2.China Academy of Railway Sciences，Beijing 100081, China） |
|
|
|
|
Abstract Abstract：Research purposes： The upwarp deformation of longitudinal connected track slab is one of the major disease forms of CRTS Ⅱ slab track in China at present. Based on the combination of differential equation method and energy method, adopting the track bending deformation patterns with sing-wave, the stability analysis models of longitudinal connected straight track slab and curved track slab which is considering vertical curve are established, and the formula of stability calculation is deduced, and the influence regularity of the parameters related to the stability of the track slab is studied. Research conclusions： (1) For CRTS Ⅱ slab ballastless track, the theory of stability of CWR (continuous welded rail) should be used to analyze the stability of longitudinal connected tack slab, and obtain the minimum critical temperature rise amplitude of the track slab, providing the basis for the stress free temperature of the slab during construction. (2) The open joints or the weakening between track slab and the interface of mortar is the most immediate cause of the upwarp deformation of longitudinal connected track slab. The reduction of the bond strength of CA mortar will lead to the 〖HJ〗marked decline of the critical buckling load of the track slab. When the bond strength of the cement and asphalt (CA) mortar is reduced by 50%, the minimum critical slab temperature will be reduced by 25%; When the longitudinal resistance of the track slab is reduced by 50%, the minimum critical slab temperature will be reduced by 5.7% and the critical versine will increase by 38.1%. The larger the initial bending of the track slab, the lower the minimum critical slab temperature, also the critical wavelength is longer and the critical versine is reduced. The effect of the vertical curve on the stability of the track slab is very small, and the reduction of minimum critical temperature force is not more than 1%. (3)The research results clarify the mechanical mechanism of the upwarp deformation of longitudinal connectedtrack slab and the influence rules of the key parameters, which can provide theoretical reference for the stability study of CRTS Ⅱ slab ballastless track on high-speed railway.
|
|
Received: 19 October 2017
|
|
|
|
|
|
|
2018, Vol. 35 
