A vehicle body, two bogie frames and two wheelsets for each bogie frame are used to describe the railway vehicle model. The system dynamic is modeled using a 38-DOF system including the longitudinal, lateral, vertical, roll, pitch and yaw displacements. A heuristic nonlinear creep model and the elastic rail are used to simulate the wheel-rail contact. Stable movement and the corresponding limit...

We analyze the asymptotic behavior of the antiplane deformations of a fragile material reinforced by a reticulated elastic structure. The microscopic geometry of this material is described by means of two “small” parameters: the size ε of the periodic grid and the ratio δ between the thickness of each of the fibers and their period of distribution. We show that this behavior depends dramaticall...

Using positional data from video microscopy of a two-dimensional colloidal system and from simulations of hard disks, we determine the wave-vector-dependent elastic dispersion relations in glass. The emergence of rigidity based on the existence of a well defined displacement field in amorphous solids is demonstrated. Continuum elastic theory is recovered in the limit of long wavelengths which p...

In this paper we present an investigation into the calculation of the Frank elastic constants of hard platelets via molecular simulation and virial expansion beyond second order. Monte Carlo simulations were carried out and director fluctuations measured as a function of wave vector k, giving the elastic constants through a fit in the low-k limit. Additionally, the virial expansion coefficients...

We calculate the coefficient of restitution, ǫ, starting from a microscopic model of elastic disks. The theory is shown to agree with the approach of Hertz in the quasistatic limit, but predicts inelastic collisions for finite relative velocities of two approaching disks. The velocity dependence of ǫ is calculated numerically for a wide range of velocities. The coefficient of restitution furthe...

We analyze the behavior of a fragile material reinforced by a reticulated elastic unbreakable structure in the case of antiplane shear. The microscopic geometry of this material is described by means of two small parameters: the period ε of the grid and the ratio δ between the thickness of the fibers and the period ε. We show that the asymptotic behavior as ε → 0 and δ → 0 depends dramatically ...

We investigate the static and dynamic (phononic) elastic behavior of fractal-cut materials. These materials are novel in the sense that they deform by rotation of “rigid” units rather than by straining these units, can be fabricated by exploiting a simple cutting paradigm, and have properties that can be manipulated by control of the cut pattern and its hierarchy. We show that variation of frac...

It is well known that the addition of small amounts of long chain polymers produces dramatic effects on flowing fluids. A remarkable effect, recently observed experimentally, is the onset of ”elastic turbulence” in the limit of very low Reynolds number Re, provided elasticity is high enough [1]. In this regime, the polymer solution displays features typical of turbulent flows. Consequently, ela...

A model calculation of nucleon-nucleon scattering is presented, which results in an amplitude that in the elastic high energy limit realizes the Wu-Yang idea regarding the relation between the elastic form factor of the nucleon and the differential cross section; and which is consistent with the behavior of the differential cross section for the production of nucleon resonances. The calculation...

This paper is devoted to describe the deformations and the elastic energy for structures made of straight rods of thickness 2δ when δ tends to 0. This analysis relies on the decomposition of the large deformation of a single rod introduced in [7] and on the extension of this technique to a multi-structure. We characterize the asymptotic behavior of the infimum of the total elastic energy as the...