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1.
Chung Fang 《Archive of Applied Mechanics (Ingenieur Archiv)》2009,79(2):169-173
In the present study, the constitutive relations derived in the revised Goodman–Cowin theory for granular matter are shown
to imply a generalized Mohr–Coulomb criterion for impending flows. Due to the concept of microcontinuum and the incorporation
of the internal friction into the expression of the Cauchy stress tensor, a constrained equilibrium stress state characterized
by the Mohr–Coulomb criterion is yet obtained under uniform distributions of the grains. 相似文献
2.
S. E. Alexandrov E. A. Lyamina 《Journal of Applied Mechanics and Technical Physics》2005,46(6):883-890
The following two models of the plasticity theory are considered: the model with the Mohr-Coulomb yield criterion and the
classical model of the plasticity theory with a yield criterion independent of the mean stress. The deformation problem of
a plastic layer enclosed between two rotating plates is studied.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 6, pp. 136–145, November–December, 2005. 相似文献
3.
A. M. Kovrizhnykh V. D. Baryshnikov A. V. Manakov A. F. Nikitenko 《Journal of Applied Mechanics and Technical Physics》2007,48(6):871-877
It is proposed to construct long-term strength and creep relations for metals on the basis of the Coulomb-Mohr criterion.
The creep equations and the long-term strength criterion for plane stress are analyzed in detail. Results of long-term strength
calculations are compared with data of experiments with metallic materials. It is established that theoretical and experimental
results are in satisfactory agreement.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 6, pp. 115–123, November–December, 2007. 相似文献
4.
Cheng Pinsan 《Acta Mechanica Sinica》1991,7(3):235-242
In this paper, a nonlocal theory of fracture for brittle materials has been systematically developed, which is composed of
the nonlocal elastic stress fields of Griffith cracks of mode-I, II and III, the asymptotic forms of the stress fields at
the neighborhood of the crack tips, and the maximum tensile stress criterion for brittle fracture. As an application of the
theory, the fracture criteria of cracks of mode-I, II, III and mixed mode I–II, I–III are given in detail and compared with
some experimental data and the theoretical results of minimum strain energy density factor. 相似文献
5.
The theory of long-term damage of homogeneous materials is generalized to particulate composite materials. The damage of the
composite components is modeled by randomly dispersed micropores. The damage criterion for a microvolume is characterized
by its stress-rupture strength. It is determined by the dependence of the time to brittle failure on the difference between
the equivalent stress and its limit, which is the tensile strength, according to the Huber–Mises criterion, and assumed to
be a random function of coordinates. An equation of damage (porosity) balance in the composite components at an arbitrary
time is formulated. Algorithms of calculating the time dependence of microdamage and macrostresses or macrostrains are developed
and relevant curves are plotted in the case of unlimited microdurability
Translated from Prikladnaya Mekhanika, Vol. 44, No. 11, pp. 7–17, November 2008. 相似文献
6.
Yu. I. Lelyukh 《International Applied Mechanics》2007,43(12):1396-1405
Three methods to allow for damage of isotropic materials are discussed. The relations of the theory of deformation along paths
of small curvature are used as equations of state. Rabotnov’s scalar equation is used to study the damage of a material during
thermoviscoelastoplastic deformation. The stress determined by a stress rupture criterion that accounts for the stress mode
is taken as an equivalent stress. An algorithm based on the finite-element method is developed to solve three-dimensional
problems of thermoviscoelastoplasticity with allowance for material damage. The numerical results obtained are compared with
experimental data
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 12, pp. 110–121, December 2007. 相似文献
7.
The damage process is modeled by randomly dispersed micropores occurring in places of destroyed microvolumes according to
the stress-rupture microstrength, which is determined by the dependence of the time to brittle failure on the difference between
the equivalent stress and its limit, according to the Huber–Mises criterion, and is a random function of coordinates. Given
microstresses or microstrains, the equations of porosity balance at an arbitrary time are derived. Together with the macrostress–macrostrain
relationships for a discrete fibrous composite with porous components, they describe the coupled processes of deformation
and long-term damage. A specific problem with a bounded stress-rupture microstrength function is solved
Translated from Prikladnaya Mekhanika, Vol. 45, No. 1, pp. 71–81, January 2009. 相似文献
8.
S. V. Suknev 《Journal of Applied Mechanics and Technical Physics》2000,41(3):526-530
The strength of a plate with an elliptic hole under uniaxial tension or compression is estimated for arbitrary angles between
the ellipse axes and the direction of loading with the use of the gradient strength criterion. The calculated critical stress
agrees with the existing experimental data.
Institute of Physicotechnical Problems of the North, Siberian, Division, Russian Academy of Sciences, Yakutsk 677891. Translated
from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 3, pp. 163–168, May–June, 2000. 相似文献
9.
Stress intensity factors and crack deviation conditions in a brittle anisotropic solid 总被引:1,自引:0,他引:1
S. A. Nazarov 《Journal of Applied Mechanics and Technical Physics》2005,46(3):386-394
For arbitrary anisotropy in the linear manifold of singular solutions generating square-root singularities of the crack tip
stress, a special basis is introduced that possesses the same properties as in the isotropic case and provides simple integral
representations for the attributes of the energy fracture criterion, in particular, the conditions of crack deviation from
a straight path.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 3, pp. 98–107, May–June, 2005. 相似文献
10.
A theory of long-term damage of particulate composite materials under thermal load is proposed. The damage of the composite
components is modeled by randomly dispersed micropores. The failure criterion for a single microvolume is determined by its
stress-rupture strength, which, in turn, is determined by the dependence of the time to brittle failure on the difference
between the equivalent stress and its limit, which characterizes the ultimate strength according to the Schleicher–Nadai criterion.
The damage (porosity) balance equation is derived for an arbitrary time, taking the thermal effect into account. Algorithms
for calculating microdamage and macrostresses as functions of time are developed 相似文献
11.
The studies on the deformation and short-term damage of physically nonlinear homogeneous and composite materials are systemized.
A single microdamage is modeled by an empty quasispherical pore in place of a microvolume damaged in accordance with the Huber–von
Mises failure criterion. The ultimate microstrength is assumed to be a random function of coordinates. The porosity balance
equation is derived. Together with the macrostress–macrostrain relationship, it constitutes a closed-form system of equations.
The damage–macrostrain relationship and macrostress–macrostrain curves for homogeneous and composite materials are analyzed 相似文献
12.
The failure criterion for a microvolume is characterized by its stress-rupture strength. It is determined by the dependence
of the time to brittle fracture on the difference between the equivalent stress and its limit, which is the ultimate strength,
according to the Schleicher–Nadai failure criterion, and assumed to be a random function of coordinates. An equation of damage
(porosity) balance in the layers at an arbitrary time is formulated taking into account the thermal component. Algorithms
of calculating the time dependence of microdamage and macrostresses are developed. Corresponding curves are plotted. The effect
of temperature on the deformation and microdamage of the layers is studied 相似文献
13.
A numerical algorithm for strength analysis of plane structural elements with stress concentrators is developed using the
gradient strength criterion and the boundary-element method. As the first calculation test, the brittle fracture of a plate
with a circular hole in tension is evaluated. To verify the algorithm and to compare the results of analysis with experimental
data available in the literature, we consider symmetric and asymmetric problems of fracture of glass plates with a narrow
elliptic hole in tension and compression. For all the problems, the accuracy of numerical results is estimated by comparison
with analytical solutions. In comparison with the classical criteria, the use of the gradient strength criterion leads to
better agreement between theoretical estimates and experimental data.
Lavrent’ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 4, pp. 214–221, July–August, 1999. 相似文献
14.
I. S. Shivakumara Jinho Lee S. Suresh Kumar N. Devaraju 《Archive of Applied Mechanics (Ingenieur Archiv)》2011,81(11):1697-1715
The linear and nonlinear stability of double diffusive convection in a layer of couple stress fluid–saturated porous medium
is theoretically investigated in this work. Applying the linear stability theory, the criterion for the onset of steady and
oscillatory convection is obtained. Emphasizing the presence of couple stresses, it is shown that their effect is to delay
the onset of convection and oscillatory convection always occurs at a lower value of the Rayleigh number at which steady convection
sets in. The nonlinear stability analysis is carried out by constructing a system of nonlinear autonomous ordinary differential
equations using a truncated representation of Fourier series method and also employing modified perturbation theory with the
help of self-adjoint operator technique. The results obtained from these two methods are found to complement each other. Besides,
heat and mass transport are calculated in terms of Nusselt numbers. In addition, the transient behavior of Nusselt numbers
is analyzed by solving the nonlinear system of ordinary differential equations numerically using the Runge–Kutta–Gill method.
Streamlines, isotherms, and isohalines are also displayed. 相似文献
15.
A. Z. Galishin 《International Applied Mechanics》2008,44(2):158-166
The paper presents a technique to determine the axisymmetric geometrically nonlinear thermoviscoelastoplastic state of thin
shells with damages. The technique is based on the geometrically nonlinear equations that incorporate transverse-shear strains.
The equations of thermoelasticity that describe the deformation of the body’s element along paths of small curvature are used
as equations of state. The equivalent stress in the kinetic equations of damage and creep is determined from a failure criterion
that accounts for the stress mode. As an example, the geometrically nonlinear thermoviscoelastoplastic deformation of a corrugated
shell is analyzed and the time to its failure is determined
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 2, pp. 49–60, February 2008. 相似文献
16.
A theory of long-term damage of homogeneous materials under thermal load is proposed. The damage of the material is modeled
by randomly dispersed micropores. The failure criterion for a single microvolume is determined by its stress-rupture strength,
which, in turn, is determined by the dependence of the time to brittle failure on the difference between the equivalent stress
and its limit, which characterizes the ultimate strength according to the Schleicher–Nadai criterion. The damage (porosity)
balance equation is derived for an arbitrary time, taking the thermal effect into account. Algorithms for calculating microdamage
and macrostresses as functions of time are developed, and respective curves are plotted. The effect of temperature on the
macrodeformation and damage curves is studied 相似文献
17.
M. V. Mir-Salim-zade 《Journal of Applied Mechanics and Technical Physics》2008,49(6):1030-1039
A problem of fracture mechanics on crack nucleation in a reinforced plate attenuated by a periodic system of circular holes
is considered. Crack nucleation is modeled by a pre-fracture band in the plastic flow state with a constant stress, which
is considered as a region of attenuated bonds between material particles. Determining unknown parameters characterizing the
emerging crack reduces to solving a singular integral equation. The condition of crack emergence is formulated with allowance
for the criterion of the limiting opening of the faces of the material pre-fracture band.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 6, pp. 170–180, November–December, 2008. 相似文献
18.
Li-Chun Bian Zouheir Fawaz Kamran Behdinan 《Archive of Applied Mechanics (Ingenieur Archiv)》2007,77(11):809-821
The maximum energy release rate criterion, i.e., G
max
criterion, is commonly used for crack propagation analysis. This fracture criterion is based on the elastic macroscopic strength
of materials. In the present investigation, however, the G
max
criterion has been modified in order to accommodate the consideration of plastic strain energy. This modified criterion is
extended to study the fatigue crack growth characteristics of mixed-mode cracks. To predict crack propagation due to fatigue
loads, a new elasto–plastic energy model is presented. This new model includes the effects of material properties such as
strain hardening exponent n, yield strength σ
y
, and fracture toughness and stress intensity factor ranges. The results obtained are compared with those obtained using the
commonly employed crack growth law and the experimental data. 相似文献
19.
D. N. Gorelov 《Journal of Applied Mechanics and Technical Physics》2006,47(1):61-67
Criteria for the separation of unsteady flow past a closed smooth airfoil are studied using the ideal fluid model and the
Brillouin-Villat criterion. The necessary separation conditions are formulated.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 1, pp. 74–81, January– February, 2006. 相似文献
20.
A methodology is developed which combines the basics of reinforced concrete, three-dimensional plasticity, stress freezing
and the shear-difference method and utilizes the maximum-tensile-stress criterion to predict crack locations and their direction
of propagation in reinforced axisymmetric specimens. The advantages of using a three-dimensional photoelastic model include:
(1) the generation of stress trajectories, (2) the accurate location of singular zones and stress concentrations, and (3)
the direct observation of internal cracks.
Paper was presented at the 1983 SEM Spring Conference on Experimental Mechanics held in Cleveland, OH on May 15–20. 相似文献