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- Timoshenko beam elements. The rail...

In present study, a mathematical model of the vehicle–floating slab track (FST) interaction is established to investigate the coupled behaviour of vehicle–track system. The FST is modelled as the double Euler -Bernoulli beam including the rail and slab. The railway vehicle is simplified as a multi-rigid-body model. The wheel–rail interface is treated using a nonlinear Hertzian contact model, co...

The finite-element method is used to perform an accurate numerical study of the normal indentation of an elastic-plastic half-space by a rigid sphere. The effects of elasticity and strain-hardening rate of the half-space are explored, and the role of friction is assessed by analysing the limiting cases of frictionless contact and sticking friction. Indentation maps are constructed with axes of ...

Osteoporosis is a well recognized problem affecting millions of individuals worldwide. The ability to diagnose problems in an effective, efficient, and affordable manner and identify individuals at risk is essential. Site-specific assessment of bone mechanical properties is necessary, not only in the process of fracture risk assessment, but may also be desirable for other applications, such as ...

Vibro-Acoustic Modulation method for detection and characterization of various structural material flaws has been actively researched the last two decades. Most studies focused on monitoring macro-cracks requiring well established baseline (no-damage) value modulation index. The is specific a particular structure, measuring setup, other factors can't be in many practical situations without long...

This work presents a finite element study of elasto-plastic hemispherical contact. The results are normalized such that they are valid for macro contacts (e.g., rolling element bearings) and micro contacts (e.g., asperity contact). The material is modeled as elastic-perfectly plastic. The numerical results are compared to other existing models of spherical contact, including the fully plastic c...

We report on observations of the electrical transport within a chain of metallic beads (slightly oxidised) under an applied stress. A transition from an insulating to a conductive state is observed as the applied current is increased. The voltage-current (U –I) characteristics are nonlinear and hysteretic, and saturate to a low voltage per contact (0.4 V). Our 1D experiment allows us to underst...