WE CONSIDER quasistatic motion and stability of a single degree of freedom elastic system undergoing frictional slip. The system is represented by a block (slider) slipping at speed V and connected by a spring of stillness k to a point at which motion is enforced at speed V,. We adopt rate and state dependent frictional constitutive relations for the slider which describe approximately experime...

Résumé. Using a high speed camera, we study the peeling dynamics of an adhesive tape under a constant load with a special focus on the so-called stick-slip regime of the peeling. It is the first time that the very fast motion of the peeling point is imaged. The speed of the camera, up to 16000 fps, allows us to observe and quantify the details of the peeling point motion during the stick and sl...

Stick-slip friction was observed in articular cartilage under certain loading and sliding conditions and systematically studied. Using the Surface Forces Apparatus, we show that stick-slip friction can induce permanent morphological changes (a change in the roughness indicative of wear/damage) in cartilage surfaces, even under mild loading and sliding conditions. The different load and speed re...

A tire and landing gear test facility has been developed and incorporated into a Convair 990 aircraft. The system can simulate tire vertical load profiles to 250,000 lb, sideslip angles to 15 degrees, and wheel braking on actual runways. Onboard computers control the preprogrammed test profiles through a feedback loop and also record three axis loads, tire slip angle, and tire condition. The ai...

A variety of rock engineering problems including drilling, cutting, abrasion and milling involve rock-tool contact and indentation. The pattern of indentation fractures and the role of slip conditions, surface roughness, tool radius, and initial aw size for an arbitrarily loaded contact are not fully known. The present paper aims to identify the elastic stress eld for a contact subjected to bot...

This paper presents the dynamic performances of an indirect vector controlled induction motor (IVCIM) using a fuzzy logic (FL) based model reference adaptive control (MRAC) slip gain tuner for speed regulation in the drive. In high performance AC drives the motor speed should closely match with the specified reference speed irrespective of the variations in the load, motor parameters and model ...

The plane strain problem of a curved elastic body pressed against an elastic half-space is considered. The effect of adhesion is included through the use of surface energy in a manner similar to the well-known JKR theory for spherical contacts. The compressive normal force is held constant while a tangential force is gradually increased from zero. The contact is characterized by complete stick ...

We estimate the loading rate in southern California and the change in stress induced by a transient slip event across the San Andreas fault (SAF) system in central California, using a model of static fatigue. We analyze temporal properties of aftershocks in order to determine the time delay before the onset of the power law aftershock decay rate. In creep-slip and stick-slip zones, we show that...

When a frictional interface is subject to a localized shear load, it is often (experimentally) observed that local slip events initiate at the stress concentration and propagate over parts of the interface by arresting naturally before reaching the edge. We develop a theoretical model based on linear elastic fracture mechanics to describe the propagation of such precursory slip. The model’s pre...

The experimental study introduces an unload-induced direct-shear model to investigate the frictional slip of a layer of simulated granular gouges induced by the combination of a decreasing normal stress and a constant shear stress. A frictional equilibrium state of the gouge layer is initially established under fixed normal and shear stresses. The normal stress is proposed to decrease at a cons...