Optimization of inter-slab joints in longitudinally connected slab ballastless track structures for temperature stress release
He An
LIU Yu
WANG Junyi
LIN Jinzhen
XU Yang
ZHAO Guotang
Abstract：To address the problem of thermal buckling at joints in longitudinally connected slab ballast-less track structures caused by excessive thermal stress accumulation under high-temperature condi-tions,this study proposes an optimization method for the inter-slab joints in longitudinally connected slab ballastless track.A thermal damage calculation model for longitudinally connected slab ballastless track structures on bridges is established.The matching relationship between the width and elastic modulus of the elastic material used for joint replacement is analyzed.The effects of the equivalent elastic modulus of the joints on thermal stress,thermal deformation,compressive damage at the joints,and interfacial damage are systematically investigated,and a recommended value for the equiva-lent elastic modulus is proposed.The results indicate that,for a given width of elastic material,a lower elastic modulus leads to greater release of longitudinal thermal stress,while resulting in greater longitudinal deformation of the track structure,increased vertical deformation reduction at the joint,and higher compressive and interfacial damage.It is recommended that the equivalent elastic modulus of the joints be set at 28 400 MPa,corresponding to a total elastic material width of 50 mm and an elas-tic modulus of 17 324 MPa.Compared to the original track structure,the replacement of both sides of the wide joint with elastic material reduces the longitudinal thermal stress by 14.2%,the compressive damage at the joints by 7.4%,the interfacial damage by 3.2%,and the vertical deformation of the joint by 2.8%.
Keywords：track engineeringlongitudinally connected slab ballastless trackinter-slab jointthermal stress releasejoint compressive damageinterfacial damage
Publication Date：2025-04-30
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：10( 135-144 )