Slip-rate-dependent melt extraction at oceanic transform faults

2015 ◽  
Vol 16 (2) ◽  
pp. 401-419 ◽  
Author(s):  
Hailong Bai ◽  
Laurent G. J. Montési
Keyword(s):  
Slip Rate ◽  
Transform Faults ◽  
Melt Extraction ◽  
Rate Dependent

Modeling of Tread Block Contact Mechanics Using Linear Viscoelastic Theory3

2008 ◽  
Vol 36 (3) ◽  
pp. 211-226 ◽  
Author(s):  
F. Liu ◽  
M. P. F. Sutcliffe ◽  
W. R. Graham
Keyword(s):  
High Speed ◽  
Slip Rate ◽  
Material Model ◽  
Contact Forces ◽  
Block Modeling ◽  
Rate Dependent ◽  
Linear Viscoelastic Material ◽  
Linear Viscoelastic ◽  
The Impact ◽  
Good Agreement

Abstract In an effort to understand the dynamic hub forces on road vehicles, an advanced free-rolling tire-model is being developed in which the tread blocks and tire belt are modeled separately. This paper presents the interim results for the tread block modeling. The finite element code ABAQUS/Explicit is used to predict the contact forces on the tread blocks based on a linear viscoelastic material model. Special attention is paid to investigating the forces on the tread blocks during the impact and release motions. A pressure and slip-rate-dependent frictional law is applied in the analysis. A simplified numerical model is also proposed where the tread blocks are discretized into linear viscoelastic spring elements. The results from both models are validated via experiments in a high-speed rolling test rig and found to be in good agreement.

scholarly journals Slip-rate-dependent friction as a universal mechanism for slow slip events

2020 ◽  
Vol 13 (10) ◽  
pp. 705-710
Author(s):  
Kyungjae Im ◽  
Demian Saffer ◽  
Chris Marone ◽  
Jean-Philippe Avouac
Keyword(s):  
Slip Rate ◽  
Slow Slip ◽  
Slow Slip Events ◽  
Rate Dependent ◽  
Universal Mechanism

scholarly journals On rate-dependent polycrystal deformation: the temperature sensitivity of cold dwell fatigue

2015 ◽  
Vol 471 (2181) ◽  
pp. 20150214 ◽  
Author(s):  
Zhen Zhang ◽  
M. A. Cuddihy ◽  
F. P. E. Dunne
Keyword(s):  
Stress Relaxation ◽  
Temperature Sensitivity ◽  
Slip Rate ◽  
Cyclic Stress ◽  
Load Shedding ◽  
Rate Dependent ◽  
Dwell Fatigue ◽  
Dislocation Hardening ◽  
Crystallographic Slip ◽  
Local Slip

A temperature and rate-dependent crystal plasticity framework has been used to examine the temperature sensitivity of stress relaxation, creep and load shedding in model Ti-6Al polycrystal behaviour under dwell fatigue conditions. A temperature close to 120°C is found to lead to the strongest stress redistribution and load shedding, resulting from the coupling between crystallographic slip rate and slip system dislocation hardening. For temperatures in excess of about 230°C, grain-level load shedding from soft to hard grains diminishes because of the more rapid stress relaxation, leading ultimately to the diminution of the load shedding and hence, it is argued, the elimination of the dwell debit. Under conditions of cyclic stress dwell, at temperatures between 20°C and 230°C for which load shedding occurs, the rate-dependent accumulation of local slip by ratcheting is shown to lead to the progressive cycle-by-cycle redistribution of stress from soft to hard grains. This phenomenon is termed cyclic load shedding since it also depends on the material's creep response, but develops over and above the well-known dwell load shedding, thus providing an additional rationale for the incubation of facet nucleation.

scholarly journals Analysis of a Dynamic Viscoelastic Contact Problem with Normal Compliance, Normal Damped Response, and Nonmonotone Slip Rate Dependent Friction

2016 ◽  
Vol 2016 ◽  
pp. 1-15 ◽  
Author(s):  
Mikaël Barboteu ◽  
David Danan
Keyword(s):  
Contact Problem ◽  
Frictional Contact ◽  
Slip Rate ◽  
Approximation Schemes ◽  
Discrete Approximation ◽  
Normal Compliance ◽  
Fully Discrete ◽  
Rate Dependent ◽  
Fully Discrete Approximation ◽  
Normal Damped Response

We consider a mathematical model which describes the dynamic evolution of a viscoelastic body in frictional contact with an obstacle. The contact is modelled with a combination of a normal compliance and a normal damped response law associated with a slip rate-dependent version of Coulomb’s law of dry friction. We derive a variational formulation and an existence and uniqueness result of the weak solution of the problem is presented. Next, we introduce a fully discrete approximation of the variational problem based on a finite element method and on an implicit time integration scheme. We study this fully discrete approximation schemes and bound the errors of the approximate solutions. Under regularity assumptions imposed on the exact solution, optimal order error estimates are derived for the fully discrete solution. Finally, after recalling the solution of the frictional contact problem, some numerical simulations are provided in order to illustrate both the behavior of the solution related to the frictional contact conditions and the theoretical error estimate result.

Rate-dependent, finite elasto-plastic deformation of polycrystals

1986 ◽  
Vol 407 (1833) ◽  
pp. 343-375 ◽  
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Finite Deformation ◽  
Constitutive Relations ◽  
Slip Rate ◽  
Large Strains ◽  
Rate Dependent ◽  
Crystallographic Slip ◽  
Self Consistent ◽  
Consistent Method

Based on Hill’s method, a self-consistent averaging scheme is proposed for estimating the overall, finite deformation response of polycrystalline aggregates consisting of single crystals which undergo plastic flow by rate-dependent crystallographic slip, accompanied by elastic lattice distortion. First, constitutive relations for such single crystals are developed assuming that the slip-rate and the associated resolved shear stress are governed by: (1) a power-law relation, and (2) a viscoplastic relation. Then, Hill’s idea that the constraint imposed on a single crystal by the remaining aggregates may be represented by embedding the single crystal in a homogeneous, infinitely extended matrix having the instantaneous overall moduli, is used to formulate a completely self-consistent averaging procedure, valid for rate-dependent materials at finite strains and rotations. This method includes both the Hill and the Krӧner‒Budiansky‒Wu (K. B. W.) methods as limiting cases; when rate-effects are negligible, it reduces to Hill’s self-consistent method as formulated by Iwakuma and Nemat-Nasser for finite deformations, while it reduces to a generalized finite deformation version of the K. B. W. method for strongly rate-dependent materials. Illustrative numerical examples are presented for a plane uniaxial deformation, using a two-dimensional poly crystalline model. These examples clearly show that the rate-dependent crystallographic slip on the level of single crystals produces a more stable overall behaviour of poly crystals. This supports similar results arrived at by other investigators for single crystals and for polycrystals, by using the Taylor averaging scheme. It is shown that, while Taylor’s averaging scheme gives accurate estimates of the incremental quantities at large strains, the total overall quantities differ considerably from the ones obtained by the self-consistent method.

scholarly journals A thermoviscoelastic beam model for brakes

2004 ◽  
Vol 15 (2) ◽  
pp. 181-202 ◽  
Author(s):  
J. BAJKOWSKI ◽  
J. R. FERNÁNDEZW ◽  
K. L. KUTTLER ◽  
M. SHILLOR
Keyword(s):  
Numerical Scheme ◽  
Frictional Contact ◽  
Slip Rate ◽  
Thermomechanical Behavior ◽  
Frictional Heat ◽  
Beam Model ◽  
Viscoelastic Beam ◽  
Braking System ◽  
Frictional Heat Generation ◽  
Rate Dependent

A model for the dynamic thermomechanical behavior of a viscoelastic beam which is in frictional contact with a rigid rotating wheel is presented. It describes a simple braking system in which the wheel comes to a stop as a result of the frictional traction generated by the beam. Friction is modelled with a temperature and slip rate dependent coefficient of friction. Frictional heat generation is taken into account as well as the wheel temperature evolution, and the wear of the beam's contacting end. The model is formulated as a variational inequality. A FEM numerical scheme for the model is described, implemented, and the results of numerical simulations are shown.

Sign in / Sign up

Export Citation Format

Share Document