Analysis of Dynamic Response on Slab Track for Passenger Dedicated Line

Research purposes: Based upon bearing characteristics of slab track,a dynamic model of slab track for the analysis of track structure vibration induced by high speed train is developed.By means of the Fourier Transform,vibration differential equation is obtained in the frequency and wave-number domain.The calculation formulas for dynamic displacement to track,track slab and concrete base in time and space domains are obtained by using the Inverse Fourier Transform.Combining a calculation example,the variation characteristics of the track,track slab and concrete base are studied under conditions of the different the speed,positive acceleration and negative acceleration of train. Research conclusions:The analysis results of dynamic response on the slab track show that the critical velocities exist in the track structure.The dynamic displacements of the rail,slab and concrete base to track direction become the biggest when train runs at even speed.Meanwhile,peak value of dynamic displacement occurs at different speed and acceleration under variable speed.The peak value of dynamic displace still exists at the different speed and acceleration when the train speed slows down,and the dynamic displacement of each structure will reduce at increasing positive acceleration and reducing negative acceleration and vice versa.