Research On The Structure Of Composite Sleeper Unballasted Track In Tunnel Under The Complex Geology

The Dali-Ruili railway tunnel passes through the serious geological disease place-"three high four active", which exists the influences of earthquake, water, spatial constraint, long tunnel maintenance work and other factors,the track structure properly adopts the track that features assembling type, resistance to erosion, unit form unballasted track.By analyzing structural characteristics of various unballasted track, the Dali-Ruili railway should adopt composite sleeper unballasted track, the vertical stress analysis model of the track was established, and then by using finite element the structure stress characteristics was analyzed, the effect of fastener, resin mortar, bedboard size, composite sleeper size and other parameters on track structure was analyzed; the bolts connect sleeper to road bed slab, and the stress of bolt was analyzed, then having designed the bolt diameter; the sleeper's supporting pattern was studied and related parameters were optimized; the corresponding construction process was designed.Through analysis conclusion is drawn, under the vertical force, rail's most vertical displacement occurs in the load position along the line direction, and the more far the distance from the load position in the both side is, the more small the vertical displacement is; along the sleeper length direction, the vertical displacement and bending moment of the composite sleeper come up to the max in the load position,and the middle bending moment of composite sleeper is very small, approaching zero; the fastener has the greater effect on the force and deformation of track structure, the stiffness and spacing of fastener take 50kN/mm,625mm properly; the resin mortar has the greater effect on the force arid deformation of track structure, the elasticity modulus and thickness of resin mortar should take 300Mpa,30mm separately; the bedboard width and thickness are suggested taking 3000mm,200mm separately; the composite sleeper size recommends for 2400×200×140mm; the diameter of bolt is sugggested taking 30mm.