Influence of Vehicle Number on the Dynamic Characteristics of High-Speed Train-CRTS III Slab Track-Subgrade Coupled System

Abstract

In this paper, a high-speed train–CRTS III slab track–subgrade coupled dynamic model is established. With the model, the influence of vehicle number on the dynamic characteristics of a train–CRTS III slab track–subgrade coupled system with smooth and random track irregularity conditions for conventional and vibration-reduction CRTS III slab tracks are theoretically studied and analyzed. Some conclusions are drawn from the results: (1) the largest dynamic responses of the coupled system for all items and cases are no longer changed when the vehicle number exceeds three, and three vehicles are adequate to guarantee the simulation precision to investigate the dynamic responses of the coupled system. (2) The acceleration of the car body has almost no relation with the vehicle number, and only one vehicle is needed to study the vehicle dynamics using the train–CRTS III slab track–subgrade coupled dynamic model. (3) For the conventional CRTS III slab track on a subgrade, the vehicle number has a negligible influence on the accelerations of the rail, slab, and concrete base, the positive and negative bending moments of the rail, the compressive force of the fastener, and the positive bending stress of slab, but it has a large influence on the tension force of the fastener, and the negative bending stresses of the slab and concrete base. Only one vehicle is needed to study track dynamics without considering the tension force of the fastener, the negative bending stresses of the slab and concrete base, otherwise, two or more vehicles are required. (4) For vibration reduction of the CRTS III slab track on a subgrade, the number of vehicles has some influence on the dynamic responses of all track components, and at least two vehicles are required to investigate the track dynamics.

Influence of temperature gradient of slab track on the dynamic responses of the train-CRTS III slab track on subgrade nonlinear coupled system

“…However, according to the research in Ref. 33 , the dynamic responses with 2 cars are almost identical to those with 8 cars. Thus, 2 cars are used in the submodel to improve the computation efficiency of the coupled system.…”

Research on Fatigue Damage Evolution of the Base Plate Structure of China Railway Track System III Type Slab Ballastless Track under Heavy Haul Train Load

“…Zeng Zhi-ping [18] carried out an experimental study on a full-scale model of a CRTSIII slab track structure, applied 30 million cyclic loads to the structure, and analyzed the evolutions of dynamic and static stiffness and acceleration of each layer structure after fatigue load. Xu Qingyuan [38] established a spatial dynamic model of vehicle CRTSIII slab track subgrade and studied the influence of the vehicle number on the characteristics of vehicle-track-subgrade system. Based on the self-developed preloading device, Kunlin Ma [39] studied the performance evolution and damage of SCC subjected to load together with freeze-thaw cycle.…”

Experimental and Numerical Verification of the Railway Track Substructure with Innovative Thermal Insulation Materials

“…The initiator of the research of the possibility of using the FC layer in the construction of the railway track substructure was the company iwtech Ltd. (London, UK) [ 39 ], which has been cooperating with the University of Žilina-Faculty of Civil Engineering (Žilina, Slovakia) for several years. Based on research cooperation agreement between them, thermal technical parameters [ 40 ], deformation characteristics [ 41 , 42 ], and dynamic characteristics [ 43 , 44 ] were determined for the foamed concrete layer and the possibility of its use in road subbase layers [ 45 ] or as a subbase of industrial floors [ 46 ] was assessed too. More than 10 years of scientific cooperation between them resulted in the granting of three patents in the field of application of composite foamed concrete in civil engineering structures with the aim of creating a subbase of high bearing capacity and with its minimized thickness and with uniform quality in the whole area and in the whole volume.…”