Ball impact has long been used as a repeatable source of stress waves in solids. The amplitude and frequency content of the waves are a function of the force-time history, or force pulse, that the ball imposes on the massive body. In this study, Glaser-type conical piezoelectric sensors are used to measure vibrations induced by a ball colliding with a massive plate. These measurements are compa...

The stress distribution on the tip of the cracks and the stress intensity factor on them are the main courses in the fracture mechanic. The stress intensity factor of the cracks with the different load exited and the different geometry are listed in the tables of the standard books. In all of them, the cracks are located in the central point of the plates. In the uniform edge loaded case, the c...

A finite deformation mixture theory is used to quantify the mechanical properties of the annulus fibrosus using experimental data obtained from a confined compression protocol. Certain constitutive assumptions are introduced to derive a special mixture of an elastic solid and an inviscid fluid, and the constraint of intrinsic incompressibility is introduced in a manner that is consistent with r...

The previously derived expressions for the incremental elastic coefficients of an isotropic medium under initial stress are applied to rubbertype elasticity. As a corollary an exact theory is obtained for the surface instability of such material under compression. It is found that in plane strain the incremental properties remain isotropic and are characterized by a single strain-dependent modu...

The solar torsional oscillations are considered as the response of the Reynolds stress to the time-dependent dynamo-induced magnetic eld. This picture is opposite to the so far accepted idea that it is the large-scale Lorentz force which directly drives the temporal variations of the surface rotation proole. Here, the \magnetic quenching" of the components of the Reynolds stress { viscosity ten...

I have developed a theory of contact mechanics between randomly rough surfaces. The solids are assumed to deform elastically when the stress sigma is below the yield stress sigma(Y), and plastically when sigma reaches sigma(Y). I study the dependence of the (apparent) area of contact on the magnification. I show that in most cases the area of real contact A is proportional to the load. If the r...

In this paper, we computationally implement and compare grammars of Samoan stress patterns that refer to feet and that refer only to syllables in Karttunen’s finite state formalization of Optimality Theory, and in grammars that directly state restrictions on surface stress patterns. The grammars are defined and compared in the highlevel language of xfst to engage closely with specific linguisti...

The paper compares the results of applying different fatigue failure models to surfaces that experience elastohydrodynamic lubrication (EHL) and have surface roughness features which are large compared with the equivalent smooth surface film thickness. The surface profiles used for the comparisons reported are taken from test gear surfaces used in an FZG gear test. The surface has a roughness o...

Analysis of stress distributions under lightweight wheeled vehicles Report Title In recent years, the need for reliable modeling tools for lightweight robotic systems deployed on various terrains has spurred research efforts into development of vehicle terrain interaction (VTI) models. This paper presents an analysis of rigid wheels dry sand interaction and compares experimental results with pr...