Experimental and Numerical Study on the Shear Strength and Strain Energy of Rock Under Constant Shear Stress and Unloading Normal Stress

After briefly reviewing previous work in this field, the authors propose that rupture of the chip work contact (to give a discontinuous chip) is governed by a limiting shear strain energy condition. Assuming that shear stress and strain at rupture are dependent on the compressive normal stress, a criterion for the direction of the rupture plane is deduced. Using some results given by Field and Merchant, the authors then compare their calculated direction of rupture with that experimentally observed. Some indication that the agreement is not entirely fortuitous is afforded by checking the calculated shear strain energy at fracture with that calculated from force and chip measurements.

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Numerical study of flow fields in an airway closure model

Journal of Fluid Mechanics ◽

10.1017/jfm.2011.96 ◽

2011 ◽

Vol 677 ◽

pp. 483-502 ◽

Cited By ~ 11

Author(s):

C.-F. TAI ◽

S. BIAN ◽

D. HALPERN ◽

Y. ZHENG ◽

M. FILOCHE ◽

...

Keyword(s):

Shear Stress ◽

Wall Shear Stress ◽

Normal Stress ◽

Numerical Study ◽

Stress Gradient ◽

Fluid Motion ◽

Flow Fields ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Wall Shear

The liquid lining in small human airways can become unstable and form liquid plugs that close off the airways. Direct numerical simulations are carried out on an airway model to study this airway instability and the flow-induced stresses on the airway walls. The equations governing the fluid motion and the interfacial boundary conditions are solved using the finite-volume method coupled with the sharp interface method for the free surface. The dynamics of the closure process is simulated for a viscous Newtonian film with constant surface tension and a passive core gas phase. In addition, a special case is examined that considers the core dynamics so that comparisons can be made with the experiments of Bian et al. (J. Fluid Mech., vol. 647, 2010, p. 391). The computed flow fields and stress distributions are consistent with the experimental findings. Within the short time span of the closure process, there are large fluctuations in the wall shear stress. Furthermore, dramatic velocity changes in the film during closure indicate a steep normal stress gradient on the airway wall. The computational results show that the wall shear stress, normal stress and their gradients during closure can be high enough to injure airway epithelial cells.

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Test Method for Low Temperature Viscosity of Drive Line Lubricants in a Constant Shear Stress Viscometer

10.1520/d6821-12 ◽

2012 ◽

Author(s):

Keyword(s):

Shear Stress ◽

Low Temperature ◽

Test Method ◽

Constant Shear ◽

Constant Shear Stress

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Behaviour of recompacted residual soils in a constant shear stress path

Canadian Geotechnical Journal ◽

10.1139/t09-129 ◽

2010 ◽

Vol 47 (6) ◽

pp. 648-661 ◽

Cited By ~ 7

Author(s):

S. M. Junaideen ◽

L. G. Tham ◽

K. T. Law ◽

F. C. Dai ◽

C. F. Lee

Keyword(s):

Shear Stress ◽

Soil Mechanics ◽

Stress Path ◽

Experimental Program ◽

Published Data ◽

Residual Soils ◽

Constant Shear ◽

Constant Shear Stress ◽

Path Dependent ◽

Soil Behaviour

The significance of studying soil behaviour in a constant shear stress path to understand rain-induced slope failures and debris flows has long been recognized. Studies with constant shear tests have, however, been limited, and some past results from undisturbed soils appear to show stress path–dependent volume change behaviour. The present study systematically investigates the behaviour of recompacted residual soils in a constant shear stress path using a comprehensive experimental program. It is shown that the results of this test program and previously published data can be interpreted using the concepts of critical-state soil mechanics.

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