Dynamic Performance Evaluation And Parameter Study Of CRTS Ⅰ Slab Ballastless Track In Mixed Railway Line

Now in China most of the railway is using mixed passenger and freight transport mode,there also are examples of running freight train on the high-speed railway. With the increaseof vehicle axle load and speed, the interaction force between wheel and rail will strengthencontinuously; the destruction of the track structure will significantly increase. If no reasonablemeasures are taken, it will make the day-to-day maintenance workload increase, shorten theservice life of track. It is necessary to execute the dynamic response analysis of ballastlesstrack. Only the scientific and reasonable structural design can improve the wheel/rail dynamicinteraction to ensure transportation safety and operation efficiently.By using the finite element analysis software ANSYS/LS-DYNA, this thesis establishthe coupled dynamic model of the vehicle-CRTSⅠslab ballastless track. In the process ofmodeling, model structures are reasonable simplified; Hertz contact theory used to equivalentlinearization the wheel/rail nonlinear contact stiffness; Track irregularity use Germany trackinterference spectrum. Based on this model, this paper studies the dynamic response ofpassenger/freight cars and CRTS Ⅰ type plate system; executes dynamics performanceevaluation of the vehicle-orbit coupling system; analyzes parameters each part of the trackstructure. In this paper following conclusions are gotten:1. Under the two conditions, when the vehicle gradually approached the orbitalcalculations point, the deformation of the track structure will be significantly increased,vibration frequency and amplitude will also increase to formation of the peak, track structurethe exhibit oscillatory changes as the wheels close to and away from. Freight compare topassenger cars, the amplitude of the individual parameters are larger in the range of60%~90%, but the change of frequency is smaller.2. Through the analysis of data, the dynamic performance indicators of thepassenger/freight cars are conformed to the rules in our country. But in comparison, thefreight condition is the most unfavorable condition in the railway. The indicators of wheel-railforce, body vibration acceleration, and load shedding rate are much higher than the passengercar conditions.3. By analyzing parameters of the model, this thesis draws the influence degree ofdifferent parameters in the track structure, and suggests reasonable range of the fourparameters: the fastener stiffness is65~85kN/mm; the slab elastic modulus is35000~45000MPa, the CA mortar elastic modulus is200~300MPa; the base plate elasticmodulus is32000~37500MPa.This paper argues that the CRTSⅠslab ballastless track can basically meet the demandof mixed passenger and freight railway line. But the most unfavorable working condition is from the freight line, which the cause of dynamic response will be fiercer. It is an inevitabletrend to separate the passenger and freight line, as the efficiency of railway transportation willenhance and the contradiction of rail transport will greatly ease.