Broken rails are the most frequent cause of freight-train derailments in the United States. Consequently, reducing their occurrence is a high priority for the rail industry and the U.S. Federal Railroad Administration. Current practice is to periodically inspect rails to detect defects using nondestructive technology such as ultrasonic inspection. Determining the optimal rail inspection frequen...

The effect of the discontinuity of the rail ends and the presence of lower modulus insulation material at the gap to the variations of stresses in the insulated rail joint (IRJ) is presented. A three-dimensional wheel – rail contact model in the finite element framework is used for the analysis. It is shown that the maximum stress occurs in the subsurface of the railhead when the wheel contact ...

The aim of this study was to compare the effects of grab rail position, orientation, and number of hands used on the kinetics of assisted sit-to-stand transfers. Participants were 12 able-bodied older adults between the ages of 69 and 88 years. While each one performed the sit-to-stand transfer, a motion analysis system with 9 cameras recording at 60 Hz tracked the 3-D trajectories of retrorefl...

Abstract MOS Current-Mode Logic (MCML) is usually used for high-speed applications. However, almost all MCML circuits are realized with dual-rail scheme. The dual-rail logic circuits increase extra area overhead and the complexity of the layout place and route. Moreover, little standard cells of the dualrail logic circuits have been developed for place-and-route tools, such as Cadence Encounter...

the main design criteria of ballasted railway tracks include rail deflections, rail bending stresses, rail wheel contact stresses, sleeper bending moments and ballast sleeper contact pressures. numerous criteria have been defined for the design of ballasted railway tracks owing to the various mechanical properties of track components and their complex interaction. therefore, railway track desig...

Ultrasonic techniques have been used for many years for the inspection of rail. These measurements can detect the presence of a wide variety of defects but there are practical difficulties with the technology. While large transverse cracks of the type likely to cause catastrophic failure can be detected, the large, critical defects can be masked by large numbers of small, surface defects along ...

The ability to perform rolling contact fatigue (RCF) experiments in wheel–rail material is provided by a new small–scale test rig, manifesting the actual dynamic behaviour of the railway system. In this paper, a multi-body dynamics (MBD) model is proposed, simulating the vibration behaviour of the prescribed rig. The new testing facility is modelled using a three-dimensional model of the vehicl...

Safety levels at highway – rail level crossing locations continue to be a major concern at most of developing countries. Basically more than half of these accidents occur at public crossings, where active warning devices are in place and functioning properly. In most cases, accidents occurred when road users ignored the gates and passed through them or if they stopped on the tracks before the g...

Investigation of vertical vibrations of a railway turnout is important in designing track components under moving loads of trains. In this paper, the turnout is simulated by a linear finite element model with modal damping. A section of the turnout has a length of 36 sleeper spans surrounding the crossing. Rails and sleepers are modeled with uniform Rayleigh-&#10Timoshenko beam elements. The ra...