Analysis Of The Mechanical Properties Of The New Embedded Track Of Tram

This article summarizes a large number of domestic and foreign scholars on the trams embedded track,on the basis of research status,using commercial software ABAQUS and the finite element software ANSYS analyses the mechanical properties of the embedded track structure.The dynamic stiffness test and fatigue test of the designed track structure are carried out.Then,based on the dynamic software SIMPACK software,the model of the train dynamics model is established,and the dynamic response of the track is obtained by using the wheel and rail force as the model of orbital dynamics calculation.The main conclusions of this paper are as follows:(1)The size of PVC pipe in the track groove has little effect on the vertical and lateral displacement of the rail,so the PVC pipe can be used to save the filling material.(2)The support rail rail groove bottom pouring the thickness of the filler material impact on the vertical equivalent stiffness fastener is larger,on the contrary,that has no influence on the lateral equivalent stiffness.Vertical equivalent stiffness increases with the increase of elastic modulus and linear.The filler material on the structure of the support rail groove in layered casting and take into accunt convenient construction and stiffness requirements,lower filler material elastic modulus values range appropriate for 2 to 3 MPa,the corresponding lateral stiffness for 30 to 40 kN/mm,upper elastic modulus values range appropriate for 12 to 15 MPa,corresponding to the vertical stiffness of 20 to 60 kN/mm.(3)Dased on polyurethane material test data compression and phenomenological theory analysis,support rail groove of the upper modified polyurethane filler material nonlinear constitutive model can take advantage of the fitting Polynomial strain energy function,and the lower modified polyurethane filler material nonlinear constitutive model can use Ogden strain energy function fitting.Considering the nonlinear constitutive model and the linear constitutive model of the filling material,the nonlinearity of the filling material has no effect on the performance of the orbital mechanics.Different pouring schemes have little influence on the rail displacement based on the lower and lower castings.(4)The dynamic stiffness test of the track structure was carried out by means of a layered structure specimen,which the bottom of the rail was 20 mm thick.The experimental consequences show that average static stiffness of the layered specimen is 49.1kN/mm and the dynamic stiffness value is directly proportional to the loading frequency.The dynamic stiffness is proportional to the loading frequency,and the dynamic stiffness ratio increases with the increase of loading frequency.The dynamic stiffness and dynamic stiffness ratio of specimen are non-linear.(5)After 3 million cyclic loading,the structural parts are not damaged and the bottom filling material is not crushed,but only the filling material and the concrete bond failure.Before and after the fatigue test of orbital structure,the static stiffness is obviously different and the static stiffness increases,while the dynamic stiffness remains unchanged.After unloading,the gauge of the structure change was 0.475 mm.(6)Employing the SIMPACK software,a tram dynamic model was established.Based on the track spectrum and rail contact model,the rail force of the train at a speed of 70km/h was obtained.The dynamic response of the orbital structure was obtained by establishing the orbital dynamics model with the lateral stiffness of 30kN/mm and vertical stiffness of 50kN/mm.