Structure Selection And Dynamic Research Of Polyurethane-stabilized Ballast Bed

ABSTRACT:Ballasted track bed is mainly used in ordinary railway and heavy haul railway in our China, the high-speed railway which reconstructed by existing railway line are all adopt ballast track bed. Although unballasted track bed is applied in almost all the newly built high-speed railway line, the ballast track bed is irreplaceable due to the advantanges of high speed in building. low cost, wide range of applications. With the operation of ballast track, there are more and more ballast contamination and powder. Frost boiling and mud pumping happens when situation deteriorate.Therefore, periodic maintanence is needed. Currently, in order to prolong the service time, A newly track bed is invented. Polyurethane is poured and turn into a foam station in ballast track bed in order to advance the mechanical property.Polyurethane-stabilized ballast bed is formed by bonding ballasts using high-agglutinating value glue. It has advantages like lightening ballast contamination and powder, reducing maintance cost. It is used in location which is different to maintain like ballast track bed in turnel, bridge and ballast track bed between two unballast track. But the construction cost is quite high. Thus it is important to make sure the right size of polyurethane-stabilized ballast bed and do some kinematic analysis to polyurethane-stabilized ballast bed.Research is done as follows:(1) Based on finite-element method and vehicle-track kinematic theory, vehicle-track-foundation model is built in this paper.(2) Comparation is done between polyurethane-stabilized ballast bed and normal ballast track bed.(3) Dimension of polyurethane-stabilized ballast bed section is studied by compared the kinematic analysis of ballast bed with different polyurethane size.(4) Influence of modulus, velocity, axle load is studied to make sure the polyurethane-stabilized ballast bed is suitable in every condition.(5) Research is done between different foundation with same pouring size in this paper to offer theory support for transition section.(6) Conclusions and advices is drawn to offer theory support for the use of polyurethane-stabilized ballast bed...