Influences of dynamic material properties of slab track components on the train-track vibration interactions

Over last two decades, the techniques of magnetically driven quasi-isentropic compression and launching high velocity flyer plates based on pulsed high current generators have being extensively used to do dynamic material experiments under extreme conditions, such as high pressure, high temperature and high strain rate. A compact pulsed power generator CQ-4 was developed to do quasi-isentropic compression experiments of materials at Institute of Fluid Physics of CAEP, which can deliver maximum peak current of about 4 MA to short-circuit loads and produce approximate 100 GPa pressure on the metallic samples. On CQ-4, several types of dynamic material experiments have being conducted for equation of states, phase transitions, constitutive relationships, micro-structure evolutions of matter under quasi-isentropic compression and shock loadings. Meanwhile the dynamic behaviors of solid plastic bonded explosives and their components have also being researched for better understanding the interaction of explosive components under stress waves and the hot spot originations and evolutions mechanism of PBX explosives under dynamic loadings. Several typical applications in dynamic material properties were shown in this paper to exhibit the capabilities of CQ-4.

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Study on the Mechanical Properties of High Performance Hybrid Fiber Reinforced Cementitious Composite (HFRCC) under Impact Loading

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.629-630.79 ◽

2014 ◽

Vol 629-630 ◽

pp. 79-84 ◽

Cited By ~ 1

Author(s):

Hui Xian Yang ◽

Jing Li ◽

Yan Sheng Huang

Keyword(s):

Impact Loading ◽

Material Properties ◽

High Performance ◽

Steel Fibers ◽

Cementitious Composites ◽

Peak Strain ◽

Fiber Reinforced ◽

Hybrid Fiber ◽

Dynamic Material Properties ◽

Fiber Reinforced Cementitious Composites

The dynamic material properties of high performance hybrid fiber reinforced cementitious composites (HFRCC) with various volumetric fractions of steel and polyvinyl alcohol (PVA) fibers were studied by the Split Hopkinson Press Bar (SHPB) test. The results show that HFRCC with higher volumetric fraction of steel fibers are more sensitive to stain rate and the dynamic compressive strength increase more prominently with the strain rate increasing, but peak strain shows the opposite trend. The PVA fibers increase the ductility of HFRCC more effectively than steel fibers. Compared to PVA fiber reinforced cementitious composites (FRCC), HFRCC present better dynamic material properties under impact loading.

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Vertical Dynamic Analysis of Ballastless Tracks on Train-Track- Bridge System

MATEC Web of Conferences ◽

10.1051/matecconf/202030602003 ◽

2020 ◽

Vol 306 ◽

pp. 02003

Author(s):

Haoran Xie ◽

Bin Yan ◽

Jie Huang

Keyword(s):

Track Structure ◽

Vertical Acceleration ◽

Train Track ◽

Steel Spring ◽

Slab Track ◽

Ballastless Track ◽

Track System ◽

Train Speed ◽

Track Bridge ◽

Bridge System

In order to investigate the vertical dynamic response characteristics of train-track-bridge system on CWR (Continunously Welded Rail) under dynamic load of train on HSR (High-Speed Railway) bridge. Based on the principle of vehicle train-track-bridge coupling dynamics, taking the 32m simply supported bridge of a section of Zhengzhou-Xuzhou Passenger Dedicated Line as an example, the finite element software ANSYS and the dynamic analysis software SIMPACK are used for co-simulation, and bridge model of the steel spring floating slab track and the CRTSIII ballastless track (China Railway Track System) considering the shock absorbing steel spring, the limit barricade and the contact characteristics of track structure layers are established. On this basis, in order to study the dynamic response laws of the design of ballastless track structure parameters to the system when the train crosses the bridge and provide the basis for the design and construction, by studying the influence of the speed of train on the bridge, the damage of fasteners and the parameters of track structure on the train-track-bridge system, the displacement of rail, vertical vibration acceleration and wheel-rail force response performance are analyzed. Studies have shown that: At the train speed of 40 km/h, the displacement and acceleration of the rail and track slab in the CRTSIII ballastless track are smaller than the floating slab track structure, but the floating slab track structure has better vibration reduction performance for bridges. The acceleration of rail, track slab and bridge increases obviously with the increase of train speed, the rail structure has the largest increasement. Reducing the stiffness of fasteners could decrease the vertical acceleration response of the steel spring floating slab track system, the ability to absorb shock can be enhanceed by reducing the stiffness of the fastener appropriately. Increasing the density of the floating slab can increase the vertical acceleration of the floating slab and the bridge, thereby decreasing the vibration amplitude of the system.

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Improved expanding ring technique for determining dynamic material properties

Review of Scientific Instruments ◽

10.1063/1.4811658 ◽

2013 ◽

Vol 84 (6) ◽

pp. 065114 ◽

Cited By ~ 5

Author(s):

M. Z. Liang ◽

X. Y. Li ◽

J. G. Qin ◽

F. Y. Lu

Keyword(s):

Material Properties ◽

Dynamic Material Properties

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