Performance Of CRTS? Slab Ballastless Track On The High Speed Railway Bridge

With China's new high-speed railway have been opened,China's "four vertical and four horizontal" high-speed railway network has been basically formed.CRTS?ballastless track in China's high-speed railway construction in the use of the longitudinal structure stress mechanism is complex.Combining with the characteristics of high proportion of China's high-speed rail line bridge,CRTS? slab track structure on bridge mechanical behavior research.Theoretical and experimental study results show that the beam body flexible conditions under bridge CRTS? slab track base slab produced additional force,expansion additional force with temperature span and the two cloth a film increases with increasing friction coefficient,and not easy to dissipate.Ballastless track stress of both grew up temperature span continuous beam and adjacent simply supported beam is relatively large.Through both the base board design load combination on the base slab and different temperatures across the longbridge expansion additional force analysis,it is proposed that the design load combination of base slab should be included in the extension and the corresponding combination coefficient.Through the establishment of full scale large test platform to verify the CRTS? slab track base slab design actual stress curve can not accurately reflect the normal work.For straight line segment base slab and the combination of the structure of the cross section vertical stiffness and cracking characteristics,test equivalent to simulate the base slab,ballastless track composite structures as a stress component under temperature load of section stiffness and cracking pattern.To study and put forward the base slab in tension,transformation of tension and compression,the compression stage and composite structure in tension and compression stage the section stiffness of suggested values,as well as cooling the base slab and the track slab under the condition of V groove,slab crack width recommended value of the side seams.Based on the scene CRTS? slab track fracture damage research results,for the CRTS? slab track structure longitudinal stiffness causes discontinuous research,The two main factors of the crack damage,the interface between the slab and the mortar layer are analyzed,and the weak links of each factor are also analyzed.In the aspect of the influence of longitudinal stiffness discontinuity,the relationship between the seam area of the mortar layer and the stress level of the longitudinal steel bar in the end of the track slab and the amount of the seam at the end of the slab is studied,and the limit value of the yield of the longitudinal steel bars in the slab end is also presented.Finally,research and analysis the influence factors of CRTS? slab track initial eccentric orbit,consider working condition of track slab overall temperature 45??According to different creep Arch of beam body and percentage of mortar layer,theoretical analysis of track slab vertical buckling critical mortar layer interface bond strength.In view of the working condition of adjacent bridge differential settlement,compared the longitudinal beam joints the effect on the stability of the vertical shear pin to track slab.Theoretical analysis is in good agreement with the experimental results,so it is concluded that the defect of the narrow joint of the slab and the bond strength of the mortar layer are the main factors that affect the arch of the slab.