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The aim of this study was to understand the stick-slip properties of single and multiple yarn pull-out in dry and treated polyester satin woven fabric in boundary regions.

Polyester satin pattern woven fabric was used to conduct the pull-out tests in order to examining the kinetic region of the force-displacement curve. Data generated from this research help the authors to obtain stick-slip force and accumulative retraction force.

It was found that stick-slip force and accumulative retraction force depend on the number of pulled ends in the fabric, fabric sample dimensions and softening treatments. Stick-slip forces of polyester satin fabric in the multiple yarn pull-out test were higher than those of the single yarn pull-out test. Stick-slip force in single and multiple yarn pull-out tests in the dry polyester satin fabric was generally higher than those of the softening treated polyester satin fabric. In addition, the warp directional single and multiple yarn stick-slip and accumulative retraction forces in the dry and softening treated polyester fabrics were generally higher than those in the weft direction in the fabric edges due to fabric density. On the other hand, the amount of stick-slip force was related to the number of interlacement points in the fabric, whereas the amount of accumulative retraction force was related to fabric structural response.

The mechanism of stick-slip and accumulative retraction force of dry-treated polyester satin pattern woven fabrics were explained. This research could be valuable for development of multifunctional fabrics in technical textiles and ballistic.

This study aims to investigate the efficacy of micro dimple in inhibiting stick-slip phenomenon on the sliding guideway.

In this study, micro-dimples were fabricated by laser on surfaces of steel disk and guideway. The disks and guideways were respectively performed pin-on-disk tribological tests and working condition experiments to study differences in lubrication condition and friction stability between textured and untextured surfaces.

Micro-dimples help reduce critical sliding speed that allows contact surfaces to enter in hydrodynamic lubrication regime. This increases hydrodynamic lubrication range and narrows speed range where stick-slip phenomenon can occur, enhancing sliding guideway’s adaptability for broader working conditions. Furthermore, friction stability on the textured surface improved, lowering the occurrence possibility of stick-slip phenomenon. Finally, difference between static and kinetic frictions on the textured surface is lower relative to the untextured surface, which decreases the critical velocity when the stick-slip phenomenon occurs.

The results indicate that laser-textured micro-dimples are significantly conducive to inhibit stick-slip phenomenon, thus providing smoother movement for the guideway and eventually increasing precision of the machine.

Granular flow lubrication is developed in recent years as a new lubrication method which can be used in extreme environments, while the stick-slip mechanisms of granular flow lubrication are an urgent obstacle remains unsolved in fully establishing the granular flow lubrication theory.

A granular flow lubrication research model is constructed by the discrete element method. Using this numerical model, the mesoscopic and macroscopic responses of stick-slip that influenced by the shear velocity, and the influence of the shear velocity and the normal pressure on the vertical displacement are studied.

Research results show that movement states of granular flow lubrication medium gradually transform from the stick-slip state to the sliding state with increased shear velocity, in which these are closely related to the fluctuations of force chains and friction coefficients between granules. The stick-slip phenomenon comes up at lower shear velocity prior to the appearance of granular lift-off between the two friction pair, which comes up at higher shear velocity. Higher normal pressure restrains the dilatation of the granular flow lubrication medium, which in turn causes a decrease in the displacement.

These findings reveal the stick-slip mechanism of granular flow lubrication and can also offer the helpful reference for the design of the new granular lubrication bearing.

The paper aims to address the formulation of zirconium and oxalicum additive-based lubricants for use in slide ways to meet the demands of high positioning exactness based on reduction in stick–slip and coefficient of friction over a wide speed range and compares the same with commercially available lubricant.

An investigation into the frictional properties and stick-slip behavior of lubricating oil is carried out using linear reciprocating tribometer and correlated with ultraviolet spectroscopic analysis.

It is observed that these transition metal additive compounds support in increasing the flexibility of the molecular chains leading to improved lubricity.

The lubricant additives considered for the current study are based on transition metals zirconium and oxalicum. It is observed that these additive compounds support in increasing the flexibility of the molecular chains, leading to improved lubricity.

The purpose of this paper is to verify, experimentally, the sliding stability of cast polyamide samples under dry sliding in contact with different steel counterface roughnesses. The effect of catalyser (sodium or magnesium) and addition of internal oil or solid lubricants is investigated and a classification for coefficients of friction in relation to the polyamide intrinsic mechanical properties is discussed.

A new tribotester is designed for meso‐scale testing according to the elastic loading region of polymers. The reliability of the tribotester is verified by preliminary determination of the stick‐slip characteristics. Sliding tests for polyamide are done at 1.15‐5.15 N normal load and 0.125‐20 mm/s sliding velocity on steel counterfaces with roughness R_a=4 and 1.6 μm.

Pure polyamides sliding against rough steel show severe stick‐slip. The stick‐slip motion is eliminated in contact with smooth steel counterfaces. Magnesium catalysed polyamide has weaker mechanical properties and shows lower friction with better sliding stability compared to sodium catalysed polyamide. Internal oil lubricant is more efficient in reducing coefficients of friction than internal solid lubricants are. Surface energy measurements are related to coefficients of friction, showing the effect of internal lubrication on adhesion.

Present test results are very specific for the present tribotester configuration and should be further compared to macro‐scale testing. The choice of tribotest conditions strongly affects the sliding performance.

Present tests are done on the meso‐scale, being in between traditional macro‐scale testing and nano‐scale testing. It allows for low contact pressures avoiding the effects of frictional heating and relatively large surfaces areas including the effects of long‐range polymer structure such as internal lubrication.

Stick‐slip is characterised by an intermittent movement when two materials are sliding across each other at very low speeds. This paper describes a new method of measuring stick‐slip on knitted and woven fabrics when sliding over non‐fibrous materials. The technique uses emitter‐receiver pairs arranged at regular intervals along the full length of the fabric panel, which each visualise the irregular movement of sticking and sliding. It is found that an extensible knitted fabric exhibits either shear or micro‐slip during the stick phase, before the actual gross slip movement.

The drill string vibrations can create harmful effects on drilling performance because they generate the stick-slip phenomenon which reduces the quality of drilling and decreases the penetration rate and may affect the robustness of the designed controller. For this reason, it is necessary to carefully test the different rock-bit contact models and analyze their influences on system stability in order to mitigate the vibrations. The purpose of this paper is to investigate the effects of rock-bit interaction on high-frequency stick-slip vibration severity in rotary drilling systems.

The main objective of this study is an overview of the influence of the rock-bit interaction models on the bit dynamics. A total of three models have been considered, and the drilling parameters have been varied in order to study the reliability of the models. Moreover, a comparison between these models has allowed the determination of the most reliable function for stick-slip phenomenon.

The torsional model with three degrees of freedom has been considered in order to highlight the effectiveness of the comparative study. Based on the obtained results, it has been concluded that the rock-bit interaction model has big influences on the response of the rotary drilling system. Therefore, it is recommended to consider the results of this study in order to design and implement a robust control system to mitigate harmful vibrations; the practical implementation of this model can be advantageous in designing a smart rotary drilling system.

Many rock-bit functions have been proposed in the literature, but no study has been dedicated to compare them; this is the main contribution of this study. Moreover, a case study of harmonic torsional vibrations analysis has been carried out in well-A, which is located in an Algerian hydrocarbons field, the indices of vibrations detection are given with their preventions.

We set up an original apparatus to measure the grain grain friction stress inside a granular medium composed of sodo‐silicate‐glass beads surrounded by a water vapor atmosphere.We analyze here the influence of the physico chemistry of water on our glass beads and its consequences on our shear experiment. We found two scales in the analysis of the shear stress signal. On the microscopic scale of one bead, the experimental results show a dependence on the size of beads, on the shear rate and on humidity for the resulting stick slip signal. On the macroscopic scale of the whole assembly of beads, the behavior of the total amplitude of the shear stress depends on the size of the beads and is humidity dependent only for relative humidity larger than 80%. For high degrees of humidity, on the microscopic scale, water lubricates the surface of the beads leading to a decrease in the microscopic resistance to shear while on the macroscopic scale the resistance to shear is increased: the assembly of very humid grains behaves as a rheothickening fluid.

Finite element implementations of the classical (stick‐slip) and a regularized (elastic‐slip) friction laws are compared for a class of non‐linear slip criteria. The fully implicit method is used for integrating the friction law. A novel implementation of the stick‐slip law, that involved transformation to a non‐orthogonal coordinate system at each contact point, is assessed. A numerical comparison is carried out for a simple problem, that has previously been analysed in the literature. The convergence of the elastic‐slip law for increasing stiffness is evaluated in addition to convergence behaviour of the adopted Newton iterations for a given law.

Large displacement misalignment under the action of active faults can cause complex three-dimensional deformation in subway tunnels, resulting in severe damage, distortion and misalignment. There is no developed system of fortification and related codes to follow. There are scientific problems and technical challenges in this field that have never been encountered in past research and practices.

This paper adopted a self-designed large-scale active fault dislocation simulation loading system to conduct a similar model test of the tunnel under active fault dislocation based on the open-cut tunnel project of the Urumqi Rail Transit Line 2, which passes through the Jiujiawan normal fault. The test simulated the subway tunnel passing through the normal fault, which is inclined at 60°. This research compared and analyzed the differences in mechanical behavior between two types of lining section: the open-cut double-line box tunnel and the modified double-line box arch tunnel. The structural response and failure characteristics of the open-cut segmented lining of the tunnel under the stick-slip part of the normal fault were studied.

The results indicated that the double-line box arch tunnel improved the shear and longitudinal bending performance. Longitudinal cracks were mainly distributed in the baseplate, wall foot and arch foot, and the crack position was basically consistent with the longitudinal distribution of surrounding rock pressure. This indicated that the longitudinal cracks were due to the large local load of the cross-section of the structure, leading to an excessive local bending moment of the structure, which resulted in large eccentric failure of the lining and formation of longitudinal cracks. Compared with the ordinary box section tunnel, the improved double-line box arch tunnel significantly reduced the destroyed and damage areas of the hanging wall and footwall. The damage area and crack length were reduced by 39 and 59.3%, respectively. This indicates that the improved double-line box arch tunnel had good anti-sliding performance.

This paper adopted a self-designed large-scale active fault dislocation simulation loading system to conduct a similar model test of the tunnel under active fault dislocation. This system increased the similarity ratio of the test model, improved the dislocation loading rate and optimized the simulation scheme of the segmented flexible lining and other key factors affecting the test. It is of great scientific significance and engineering value to investigate the structure of subway tunnels under active fault misalignment, to study its force characteristics and damage modes, and to provide a technical reserve for the design and construction of subway tunnels through active faults.