To study the mechanical characteristics of ballasted bed under dynamic stability, a three-dimensional discrete element model with 1000 mm × 700 550 is established based on method. Meanwhile, simulation test bench same size built for analysis and experimental research. The variation law trend settlement, lateral resistance, compactness different excitation frequencies are analyzed comprehensivel...

The saccule is known to play an important role in hearing in fishes. In this study we investigated spatial frequency selectivity of single saccular afferents in a teleost fish (the sleeper goby, Dormitator latifrons) to acoustic particle motion at 50-400 Hz. Saccular afferents have similar distributions of best sensitivity (-90.0 to -54.8 dB re. 1 g, mean +/- s.d.=-81.1+/-8.0 dB) and characteri...

An analysis of group influence processes indicates that the functional relationship between attraction to a group and influence exerted by the group depends on the importance to the individual member of any freedom that is threatened by group pressure to conform. This proposition was tested by an experiment in which the effect of group conformity pressure on public and private opinions was meas...

in this paper, the main factors in the analysis of the railway concrete sleepers areinvestigated and new recommendations are made in order to improve the accuracy of the currentpractices in analysis of the railway track system. first, a comprehensive literature survey isconducted, then, fem models for a railway track system are developed and used to discuss andevaluate the assumptions commonly ...

Ballasted tracks are common in the railway system as a means of providing necessary support for sleepers and rails. To keep them operational, tamping other maintenance actions performed based on track geometry measurements. Ballast particle rearrangement, which is caused by train load, one most important factors leading to degradation. As result, when planning maintenance, it vital predict beha...

To enhance the stability of continuous welded rail (CWR) tracks, frictional sleepers have been developed. The are new types with grooves on bottom, and different bottom improve lateral resistances at magnitudes. In this study, single sleeper push test (SSPT) its model discrete element method (DEM) were carried out to confirm how much arrowhead groove (AGF) increases resistance ballasted track. ...

the track stiffness experienced by a train will vary along the track. sometimes the stiffness variation may be very large within a short distance. one example is when an unsupported sleeper is hanging in the rail. track stiffness is then, locally at that sleeper, very low. at insulated joints the bending stiffness of the rail has a discontinuity implying a discontinuity also of the track stiffn...