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1.
A method for numerical analysis of the elastoplastic stress–strain state of thin layered shells of revolution under axisymmetric
loading is proposed. Constitutive equations describing the elastoplastic deformation of isotropic materials with allowance
for the stress mode are used. Numerical results are presented 相似文献
2.
B. D. Annin V. V. Alekhin S. N. Korobeinikov 《Journal of Applied Mechanics and Technical Physics》2000,41(5):937-944
The equations of quasistatic deformation of elastoplastic bodies are considered in a geometrical linear formulation. After
discretization of the equations with respect to spatial variables by the finite-element method, the problem of determining
equilibrium onfigurations reduces to integration of a system of nonlinear ordinary differential equations. In the ultimate
state of a body of an ideal elastoplastic material, the matrix of the system degenerates and the problem becomes singular.
A regularization algorithm for determining solutions of the problems for the ultimate states of bodies is proposed. Numerical
solutions of test problems of determining the ultimate loads and equilibrium configurations for ideal elastoplastic bodies
confirm the reliability of the regularization algorithm proposed.
Lavrent’ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 5, pp. 196–204, September–October, 2000. 相似文献
3.
Relations are proposed for the determination of the stress-strain state, strength, and life of butt welds with mild and hard
interlayers under cyclic elastoplastic tension-compression. The accumulation of cyclic and quasistatic damages is determined
with allowance for the redistribution of the cyclic elastoplastic strains and hardness of the stress state due to changes
in the cyclic properties of separate regions of welds. The theoretical distribution of cyclic strains and the durability of
welds under cyclic elastoplastic loading are supported by experimental data
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 2, pp. 29–38, February 2008. 相似文献
4.
R. A. Vasin 《Mechanics of Solids》2011,46(1):15-20
The prospects of application of A. A. Il’yushin’s theory of elastoplastic processes when studying structure-mechanical properties
of materials are discussed. It is shown that the idea to classify material strain processes by their complexity, which was
proposed in the theory of elastoplastic processes, allows one to form task-oriented data banks (DB) of structure-mechanical
properties of materials in a new way. These DB can also be used to estimate the physical reliability of solutions of boundary
value problems in the process of obtaining products with prescribed functional properties by using some information about
the structure state of the material. 相似文献
5.
Yu. N. Shevchenko R. G. Terekhov N. N. Tormakhov 《International Applied Mechanics》2006,42(4):421-430
Equations relating the components of the stress and strain tensors (constitutive equations) are formulated in terms of Euler
coordinates. The equations describe the finite elastoplastic deformation of an isotropic body along paths of small curvature.
It is assumed that the stress deviator is coaxial with the plastic-strain differential deviator. The relationships between
the first and second invariants of the stress and strain tensors in the case of complex elastoplastic deformation of the body’s
elements are determined from base tests on tubular specimens loaded along rectilinear paths for several values of the stress
mode angle. Methods for specification of these relationships are proposed. The assumptions adopted to derive the constitutive
equations are validated experimentally
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Translated from Prikladnaya Mekhanika, Vol. 42, No. 4, pp. 62–72, April 2006. 相似文献
6.
William N. Sharpe Jr. 《Experimental Mechanics》1992,32(1):62-67
In principle, one should be able to measure elastoplastic stresses in the same manner as one does elastic stresses; i.e.,
measure the strains and compute the stresses from the constitutive law. In practice, this is rarely done because of the more
complicated material response and the anisotropy of the plastic behavior. Further, elastoplastic stresses should be computed
incrementally in the general case.
This paper presents procedures for computing stresses from elastoplastic strains measured incrementally in a test under microcomputer
control. The approach is evaluated for four different materials—two obeying the assumptions of classical plasticity and two
showing anisotropic behavior—by computing the stresses in a smooth specimen from measured principal strains. A useful application
is presented by computing the stresses at a notch root from biaxial strains measured with laser-based interferometry.
The general conclusion is that even in situations where the material is clearly anisotropic, this approach can give a reasonableestimate of the largest local principal stress.
Paper was presented at the 1991 SEM Spring Conference on Experimental Mechanics held in Milwaukee, WI on June 9–13. 相似文献
7.
Relations are proposed for evaluating the stress-strain state and strength of a butt weld with a mild interlayer under elastoplastic
tension in plane-and axisymmetric-strain conditions. The relations allow for the distribution of transverse normal stresses
across the interlayer thickness and the interaction and hardening of the metals in the elastoplastic domain. The predicted
strain distribution in certain areas of the weld and its strength are verified experimentally
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Translated from Prikladnaya Mekhanika, Vol. 42, No. 4, pp. 119–127, April 2006. 相似文献
8.
H. Watanabe Kunihiro Osaki Mutsuo Matsumoto Dobrin P. Bossev Cathy E. McNamee Masaru Nakahara Ming-Long Yao 《Rheologica Acta》1998,37(5):470-485
Nonlinear rheological features were investigated for an aqueous solution of tetraethylammonium perfluorooctyl sulfonate (C8F17SO3
–N+(C2H5)4; abbreviated as FOSTEA). In the solution (c=0.045 mol/l; 28.3 g/l), spherical micelles of FOSTEA were connected with each other to form threads of pearl-necklace shape.
These threads were further organized into a transient network to exhibit linear relaxation characteristic of living polymers,
single-mode terminal relaxation widely separated from faster relaxation processes. Nonlinear relaxation experiments against
large step-strains γ(≤8) revealed that the terminal relaxation mode had a γ-insensitive relaxation time but its relaxation
intensity exhibited significant damping (much stronger than that for entangled polymers). In contrast, the relaxation time
and intensity for the fast relaxation modes first increased and then decreased with increasing γ. Under shear flow, the FOSTEA
threads exhibited strong thinning of the viscosity. These nonlinear features of the FOSTEA threads were compared with those
of other threadlike micelles, analyzed on the basis of an empirically introduced constitutive equation, and discussed in relation
to strain/low-induced scission of the living threads.
Received: 20 February 1998 Accepted: 30 July 1998 相似文献
9.
We consider a new class of elastoplastic models which are based on the assumption that internal interaction between the continuum
particles has affine-metric geometrical structure. From the physical viewpoint, the affine-metric objects are intrinsic thermodynamic
variables which describe the evolution of various defect structures in a deformable material and also interaction between
themselves and with the field of reversible strains. The analysis performed allows one to establish a relation between the
classical mechanical characteristics of elastoplastic materials and the field of dislocation density and other types of defects.
Institute of Automatics and Control Processes, Far-Eastern Division, Russian Academy of Sciences, Vladivostok 690041. Translated
from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 40, No. 2, pp. 163–173, March–April, 1999. 相似文献
10.
I. S. Chernyshenko E. A. Storozhuk S. B. Kharenko 《International Applied Mechanics》2011,47(6):679-684
The elastoplastic state of thin conical shells with a circular hole is analyzed assuming finite deflections. The distributions
of stresses, strains, and displacements along the hole boundary and in the zone of their concentration are studied. The stress–strain
state of shells around the hole under axial tension is analyzed taking into account two nonlinear factors. The numerical results
are presented as plots and tables 相似文献
11.
The elastoplastic bending of a sandwich bar with a stiff compressible core on an elastic foundation is studied. The kinematics
of the bar, which is asymmetric across the thickness, is described adopting Bernoulli’s hypotheses for the face layers. The
displacements of the core are assumed to vary linearly across the thickness. The foundation is described by the Winkler model.
A system of equilibrium equations for displacements is derived and solved. Numerical results for a metal-polymer sandwich
bar are presented
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 4, pp. 110–120, April 2007. 相似文献
12.
A method of stress—strain analysis of elastoplastic bodies with large displacements, rotations, and finite strains is developed.
The incremental loading technique is used within the framework of the arbitrary Lagrangian—Eulerian formulation. Constitutive
equations are derived which relate the Jaumann derivative of the Cauchy—Euler stress tensor and the strain rate. The spatial
discretization is based on the FEM and multilinear three-dimensional isoparametric approximation. An algorithm of stress—strain
analysis of elastic, hyperelastic, and perfectly plastic bodies is given. Numerical examples demonstrate the capabilities
of the method and its software implementation
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Translated from Prikladnaya Mekhanika, Vol. 41, No. 6, pp. 36–43, June 2005. 相似文献
13.
Yu. M. Volchkov 《Journal of Applied Mechanics and Technical Physics》2000,41(5):945-949
Numerical techniques are proposed for determining the integral characteristics of penetration of a rod into an target. An
algorithm for solving two-dimensional elastoplastic problems is employed. To construct the solution, a one-dimensional finite-element
column is used (a two-dimensional domain is replaced by a one-dimensional domain).
Lavrent’ev Institute of Hydrodynamics, Siberian Division, Russian Academy of Sciences, Novosibirsk 630090. Translated from
Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 41, No. 5, pp. 205–210, September–October, 2000. 相似文献
14.
V. I. Odinokov A. M. Sergeeva 《Journal of Applied Mechanics and Technical Physics》2006,47(2):266-273
The spatial problem of determining the stress-strain state of an ice plate of finite thickness broken by a patented method
is solved using the theory of small elastoplastic strains and a proven numerical method.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 2, pp. 139–146, March–April, 2006. 相似文献
15.
V. A. Bykov E. F. Gryaznov V. N. Okhitin 《Journal of Applied Mechanics and Technical Physics》2009,50(3):406-412
The process of projection of a layer of an ideal liquid enclosed into a cylindrical elastoplastic shell by products of instantaneous
detonation of a high explosive charge is studied numerically in a two-dimensional plane formulation. The processes of shell
fracture and liquid exhaustion through the resultant slots are considered. Numerical results are analyzed, and analytical
relations for angular distributions of radial velocity and mass of the liquid escaping through the slots are derived.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 50, No. 3, pp. 56–63, May–June, 2009. 相似文献
16.
We study the thermal force bending of an elastoplastic three-layer beam with a rigid filler; the beam is connected with an
elastic foundation. The broken normal hypothesis is adopted to describe the kinematics of a packet nonsymmetric with respect
to the thickness. The foundation reaction is described by Winkler’s model. The system of equilibrium equations and its exact
solution in displacements are obtained and numerical results for a three-layer metal-polymeric beam are presented. 相似文献
17.
I. M. Lavit Nguyen Viet Trung 《Journal of Applied Mechanics and Technical Physics》2008,49(3):491-499
The thermoelastoplastic fracture mechanics problem of a thick-walled cylinder subjected to internal pressure and a nonuniform
temperature field is solved by the method of elastic solutions combined with the finite-element method. The correctness of
the solution is provided by using the Barenblatt crack model, in which the stress and strain fields are regular. The elastoplastic
problem of a cracked cylinder subjected to internal pressure and a nonuniform temperature field are solved. The calculation
results are compared with available data.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 49, No. 3, pp. 173–183, May–June, 2008. 相似文献
18.
P. Z. Lugovoi V. F. Meish B. P. Rybakin G. V. Secrieru 《International Applied Mechanics》2008,44(7):788-793
A numerical algorithm to determine the stress-strain state of a reinforced cylindrical shell subject to impulsive loading
is elaborated. Results from a numerical analysis of the dynamic behavior of a reinforced elastoplastic shell under explosive
loading are presented
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 7, pp. 83–90, July 2008. 相似文献
19.
A. Z. Galishin 《International Applied Mechanics》2000,36(4):538-544
A technique is developed for determination of the axisymmetric thermoelastoplastic stress-strain state of branched laminated
transversally isotropic shells of revolution under loads that cause the meridional stress state and torsion. The method is
based on the rectilinear-element hypotheses for the whole package of layers. To describe the processes of active elastoplastic
deformation of a transversally isotropic material, deformation-type equations, which are constructed without recourse to the
plastic-potential existence condition, are used. The scalar functions in the constitutive equations depend on the shear-strain
rate and temperature. The solution of the problem is reduced to numerical integration of systems of differential equations.
An example of determination of the elastoplastic state of a two-layer cylindrical shell stiffened with a rigid ring support
is presented.
S. P. Timoshenko Institute of Mechanics, National Academy of Sciences of Ukraine, Kiev. Translated from Prikladnaya Mekhanika,
Vol. 36, No. 4, pp. 125–131, April, 2000. 相似文献
20.
I. S. Chernyshenko E. A. Storozhuk I. B. Rudenko 《International Applied Mechanics》2008,44(12):1397-1404
The elastoplastic state of a thin spherical shell weakened by an elliptic hole is analyzed. Finite deflections are considered.
The hole is reinforced with a thin ring. The shell is made of an isotropic homogeneous material. The load is internal pressure.
A relevant problem is formulated and solved numerically with allowance for physical and geometrical nonlinearities. The distribution
of stresses, strains, and displacements along the elliptic boundary and in the zone of their concentration is studied. The
stress–strain state of the shell near the hole is analyzed
Translated from Prikladnaya Mekhanika, Vol. 44, No. 12, pp. 93–101, December 2008. 相似文献