共查询到20条相似文献,搜索用时 15 毫秒
1.
I. S. Chernyshenko E. A. Storozhuk S. B. Kharenko 《International Applied Mechanics》2008,44(2):174-181
The elastoplastic state of conical shells weakened by an elliptic hole and subjected to finite deflections is studied. The
material of the shells is assumed to be isotropic and homogeneous; the load is constant internal pressure. The problem is
formulated and a technique for numerical solution with allowance for physical and geometrical nonlinearities is proposed.
The distribution of stresses, strains, and displacements along the hole boundary and in the zones of their concentration is
studied. The solution obtained is compared with the solutions of the physically and geometrically nonlinear problems and a
numerical solution of the linear elastic problem. The stress-strain state around an elliptic hole in a conical shell is analyzed
considering both nonlinearities
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 2, pp. 69–77, February 2008. 相似文献
2.
The elastoplastic state of thin spherical shells with an elliptic hole is analyzed considering that deflections are finite.
The shells are made of an isotropic homogeneous material and subjected to internal pressure of given intensity. Problems are
formulated and a numerical method for their solution with regard for physical and geometrical nonlinearities is proposed.
The distribution of stresses (strains or displacements) along the hole boundary and in the zone of their concentration is
studied. The results obtained are compared with the solutions of problems where only physical nonlinearity (plastic deformations)
or geometrical nonlinearity (finite deflections) is taken into account and with the numerical solution of the linearly elastic
problem. The stress—strain state in the neighborhood of an elliptic hole in a shell is analyzed with allowance for nonlinear
factors
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Translated from Prikladnaya Mekhanika, Vol. 41, No. 6, pp. 95–104, June 2005. 相似文献
3.
I. S. Chernyshenko E. A. Storozhuk S. B. Kharenko 《International Applied Mechanics》2007,43(4):418-424
The elastoplastic state of thin conical shells with a curvilinear (circular) hole is analyzed assuming finite deflections.
The distribution of stresses, strains, and displacements along the hole boundary and in the zone of their concentration are
studied. The stress-strain state around a circular hole in shells subject to internal pressure of prescribed intensity is
analyzed taking into account two nonlinear factors
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 4, pp. 73–79, April 2007. 相似文献
4.
5.
I. Yu. Tsvelodub 《Journal of Applied Mechanics and Technical Physics》2003,44(5):716-720
The following two types of physically nonlinear inhomogeneous media are considered: linear-elastic plane with nonlinear-elastic elliptic inclusions and linear-viscous plane with elliptic inclusions from a material that possesses nonlinear-creep properties. The problem is to determine infinitely distant loads that produce a required value of the principal shear stress (in the first case) or principal shear-strain rate (in the second case) for two arbitrary inclusions. Conditions for the existence of solutions of these problems for incompressible media under plane strains are obtained. 相似文献
6.
I. S. Chernyshenko E. A. Storozhuk F. D. Kadyrov 《International Applied Mechanics》2007,43(5):512-518
The elastoplastic state of isotropic homogeneous cylindrical shells with elliptic holes and finite deflections under internal
pressure is studied. Problems are formulated and numerically solved taking into account physical and geometrical nonlinearities.
The distribution of stresses (displacements, strains) along the boundary of the hole and in the zone of their concentration
is analyzed. The data obtained are compared with the numerical solutions of the physically nonlinear, geometrically nonlinear,
and linear problems. The stress-strain state of cylindrical shells in the neighborhood of the elliptic hole is analyzed with
allowance for nonlinear factors
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 5, pp. 46–54, May 2007. 相似文献
7.
The paper proposes a unified approach to problems of stress concentration near notches with sharp and rounded tip based on
the method of singular integral equations. A solution for an elastic region having a V-shaped notch with rounded tip of large
curvature is first found. Then, the stress intensity factor at the tip of a sharp-tipped notch is calculated by passing to
the limit. Numerical results are obtained for a slit and a square hole in an elastic plane and an edge notch in a half-plane
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 2, pp. 70–87, February 2007.
For the centenary of the birth of G. N. Savin. 相似文献
8.
Summary The paper deals with numerical solutions of singular integral equations in stress concentration problems for longitudinal
shear loading. The body force method is used to formulate the problem as a system of singular integral equations with Cauchy-type
singularities, where unknown functions are densities of body forces distributed in the longitudinal direction of an infinite
body. First, four kinds of fundamental density functions are introduced to satisfy completely the boundary conditions for
an elliptical boundary in the range 0≤φ
k
≤2π. To explain the idea of the fundamental densities, four kinds of equivalent auxiliary body force densities are defined
in the range 0≤φ
k
≤π/2, and necessary conditions that the densities must satisfy are described. Then, four kinds of fundamental density functions
are explained as sample functions to satisfy the necessary conditions. Next, the unknown functions of the body force densities
are approximated by a linear combination of the fundamental density functions and weight functions, which are unknown. Calculations
are carried out for several arrangements of elliptical holes. It is found that the present method yields rapidly converging
numerical results. The body force densities and stress distributions along the boundaries are shown in figures to demonstrate
the accuracy of the present solutions.
Received 26 May 1998; accepted for publication 27 November 1998 相似文献
9.
郭仲衡 《应用数学和力学(英文版)》1983,4(5):639-648
Presenting some recent considerations and results, the present paper deals with two basic concepts of the continuum mechanics: strain-and stress-rates. Upon a brief systematic survey of concepts of strain and stress, a so far unknown explicit expression for the rate of the right stretch tensor is offered in absolute notation. This paper then suggests to distinguish two ways of defining objective stress-rates. Following the second procedure, after analyzing several particular cases, the author proposes a generalized Jaumann flux, which contains the majority of the existing definitions for stress-rate and the Hill’s result as well. 相似文献
10.
Simplified equations are derived for the analysis of stress concentration for shear-deformable shallow shells with a small hole.General solutions of the equations are obtained,in terms of series,for shallow spherical shells and shallow circular cylindrical shells with asmall circular hole.Approximate explicit solutions and numerical results are obtianed forthe stress concentration factors of shallow circular cylindrical shells with a small hole onwhich uniform pressure is acting. 相似文献
11.
The structural theory of short-term damage is used to study the coupled processes of deformation and microdamage of a physically
nonlinear material in a combined stress state. The basis for the analysis is the stochastic elasticity equations for a physically
nonlinear porous medium. Damage in a microvolume of the material is assumed to occur in accordance with the Huber-Mises failure
criterion. The balance equation for damaged microvolumes is derived and added to the macrostress-macrostrain relations to
produce a closed-form system of equations. It describes the coupled processes of nonlinear deformation and microdamage of
the porous material. Algorithms are developed for calculating the dependence of microdamage on macrostresses and macrostrains
and plotting stress-strain curves for a homogeneous material under either biaxial normal loading or combined normal and tangential
loading. The plots are analyzed depending on the type of stress state
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Translated from Prikladnaya Mekhanika, Vol. 42, No. 11, pp. 30–39, November 2006. 相似文献
12.
A severe limitation on the complex variable method in plane elasticity is the requirement that the region in which the stresses
and strains are sought admits a rational conformal mapping into the half-plane or the unit circle. Of course, this limitation has not prevented the solution of many
fundamental and interesting problems. However, the extension of this method to more general regions remains a source of debate.
We here present an attempt in this direction. If the conformal mapping of the region is an algebraic function, it is still possible to find mathematical conditions defining the complex-valued stress function, but its explicit
representation now requires the solution of a singular, linear, complex-valued, integro-differential equation. 相似文献
13.
Roberta Sburlati 《International Journal of Solids and Structures》2013,50(22-23):3649-3658
The aim of this work is to present an analytical solution to reduce the stress concentration factor (SCF) around a circular hole in an isotropic homogeneous plate subjected to far-field uniaxial loading. In this paper the elastic response of an inhomogeneous annular ring made of functionally graded material (FGM), inserted around a hole of a homogeneous plate, is studied. By assuming that Young’s modulus varies in the radial direction with power law and that Poisson’s ratio is constant, the governing differential equations for plane stress conditions are obtained. Using stress function a general solution in explicit closed form is presented and the SCF investigated to highlight the inhomogeneity effects. Furthermore, the explicit solution for an inner homogeneous ring, with different properties with respect to those of the plate, is explicitly obtained and numerical results are compared between homogeneous ring and FGM ring. 相似文献
14.
15.
16.
V. P. Revenko 《International Applied Mechanics》2008,44(1):73-80
A numerical-analytical method for solving the plane problem of elasticity is proposed. Systems of nonorthogonal functions
are used. The method involves the minimization of a quadratic form that is equal to the integral of the sum of squared residuals
of the solution and given forces. An explicit expression for stresses is derived. Bessel's inequality and the convergence
of the solution are proved. The accuracy of the boundary conditions is estimated. The stress and strain distribution in the
plate depending on the maximum magnitude of distributed forces and the size of their localization area is analyzed numerically.
New quantitative and qualitative features of the stress distribution in the plate are established
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 1, pp. 90–98, January 2008. 相似文献
17.
根据Hellinger-Reissner原理建立了具有一个无外力圆柱表面的三维八节点杂交应力元,其假设应力场严格满足柱坐标下三维平衡方程及圆柱面上无外力边界条件;当元退化为二维时也满足协调方程。数值算例表明,这种特殊杂交应力元可高效地分析具有两个圆孔薄板和厚板的应力集中,特别是三维应力集中。 相似文献
18.
The structural theory of short-term damage is generalized to the case where the undamaged components of a particulate composite
deform nonlinearly under loads that induce a compound stress state. The basis for this generalization is the stochastic elasticity
equations for a particulate composite with porous components whose skeletons deform nonlinearly. Damage in a microvolume of
the material is assumed to occur in accordance with the Huber-Mises failure criterion. Balance equations for damaged microvolume
are derived for the physically nonlinear materials of the components. Together with the macrostress-macrostrain relationship
for a particulate composite with porous nonlinear components, they constitute a closed-form system of equations. This system
describes the coupled processes of physically nonlinear deformation and microdamage. Algorithms for calculating the microdamage-macrostrain
relationship and plotting stress-strain curves are proposed. Such curves are plotted for the case where the composite is subjected
to a combination of normal and tangential loads, and microdamages occur in the linearly hardened matrix and do not in the
linearly elastic inclusions. The stress-strain curves are examined depending on the volume fraction of inclusions and presence
of tangential stresses
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Translated from Prikladnaya Mekhanika, Vol. 42, No. 12, pp. 48–57, December, 2006. 相似文献
19.
为了客观反映宽翼缘梁在非线性温差作用下的自应力分布特点,克服按梁理论计算温度自应力时的不足,本文从弹性力学的分析方法入手,按平面应力状态分析翼缘板和腹板的温度应力。通过翼缘板与腹板连接处的变形协调条件及平衡条件建立补充方程,求解艾瑞应力函数中的积分常数,推导了翼缘板与腹板的纵、横向正应力、剪应力及位移分量解析式。导出的翼缘板纵向正应力公式可自动考虑宽翼缘梁沿横截面宽度自应力不均匀分布的特点。对一宽翼缘T梁的计算表明,当翼缘板相对于腹板发生温差变化时,沿其宽度的纵向温度自应力分布很不均匀,在翼缘板根部自应力较大而在悬臂端则显著减小。按通常基于梁理论的温度自应力计算方法,无法反映这种应力分布规律。 相似文献
20.
An analytical method was proposed dielectric properties for particulate composites. to calculate effective linear and nonlinear The method is based on an approximate solution of two-particle interaction problem, and it can be applied to relatively high volume concentration of particles (up to 50%). Nonlinear dielectric property was also examined by means of secant method. It is found that for low applied electric filed the proposed method is close to Stroud and Hui's method and for high applied electric filed it is close to Yu's method. 相似文献