Mechanics of Solids (about journal) Mechanics of Solids
A Journal of Russian Academy of Sciences
in January 1966
Issued 6 times a year
Print ISSN 0025-6544
Online ISSN 1934-7936

Russian Russian English English About Journal | Issues | Guidelines | Editorial Board | Contact Us

IPMech RASWeb hosting is provided
by the Ishlinsky Institute for
Problems in Mechanics
of the Russian
Academy of Sciences
IssuesArchive of Issues2007-6pp.910-918

Archive of Issues

Total articles in the database: 9179
In Russian (. . ): 6485
In English (Mech. Solids): 2694

<< Previous article | Volume 42, Issue 6 / 2007 | Next article >>
D. L. Bykov and D. N. Konovalov, "Use of structural components of specific work of internal forces for estimating the strength of viscoelastic structures in local stress concentration regions," Mech. Solids. 42 (6), 910-918 (2007)
Year 2007 Volume 42 Number 6 Pages 910-918
Title Use of structural components of specific work of internal forces for estimating the strength of viscoelastic structures in local stress concentration regions
Author(s) D. L. Bykov (Central Research Engineering Institute, Russian Space Agency, Pionerskaya 4, Korolev, Moscow Region, 141070, Russia)
D. N. Konovalov (OT-Kontakt Ltd, Aviamotornaya 2, Moscow, 111020, Russia,
Abstract Material fracture experiments on specimens and structures testify that materials can resist greater stresses in local stress concentration regions than in regions with a nearly homogeneous stress state. Taking this fact into account in design stress analysis permits one to reveal additional structure loading and/or service life margins. One approach aimed at taking into account the increased strength in local stress concentration regions is to use averaged limit characteristics parametrically depending on the characteristic size L of the averaging region. One version of this approach is the concept of "elementary block" of a material [1, 2]. The averaged limit characteristics are determined by an experiment-calculation method involving the analysis of the stress-strain state of a material specimen with a stress concentrator at the time when the specimen attains the limit state preceding macrofracture. In [3], the dependence of the averaged limit separation stresses on the size of the averaging region was determined on the basis of numerical analysis of the singular stress state of the specimen used to determine the standard characteristics of the adhesion strength of a filled polymer material. In the present paper, we generalize the above approach to the case of a viscoelastic material. For the limit characteristics of the material in the local stress concentration region we take the volume-averaged components of the specific work of internal forces [4, 5] (the averaged specific absorbed energy and the averaged specific instantaneously reversible energy). The introduction of two limit energies originates from the fact that, to initiate the process of macrofracture, it is necessary to satisfy the following two conditions simultaneously: the material must be "damaged" sufficiently strongly by the preceding loading, and the "damaged" material must be loaded sufficiently strongly. As an example of determining the material averaged limit energy characteristics in a local stress concentration region, we consider the problem about the strain of a viscoelastic specimen used to determine the standard adhesion strength characteristics. The problem is solved numerically under the following assumptions: the specimen material is assumed to be linearly viscoelastic, and the specific absorbed energy in the stress concentration region is assumed to coincide in magnitude with the specific scattered energy. To estimate the accuracy of the numerical method, we use the solution of the model problem about the action of a plane circular die on a half-space consisting of a linearly viscoelastic incompressible material.
1.  H. Neuber, Stress Concentration (Gostekhizdat, Moscow-Leningrad, 1947) [in Russian].
2.  P. Forrest, Metal Fatigue (Mir, Moscow, 1968) [in Russian].
3.  D. L. Bykov, A. M. Vasil'ev, and D. N. Konovalov, "Evaluation of the Strength of Composite Structures in Zones of Local Stress Concentration," Mekh. Komp. Mat., No. 2, 308-312 (1984) [Mech. Comp. Mater. (Engl. Transl) 20 (2), 238-242 (1984)].
4.  D. L. Bykov and D. N. Konovalov, "Nonlinear Endochronous Theory of Aging Viscoelastic Materials," Izv. Akad. Nauk. Mekh. Tverd. Tela, No. 4, 63-76 (2002) [Mech. Solids (Engl. Transl.) 37 (4), 52-62 (2002)].
5.  D. L. Bykov, "Utilization of Structural Components of Specific Work of Internal Forces for the Description of Strength of Viscoelastic Materials," Izv. Akad. Nauk. Mekh. Tverd. Tela, No. 3, 99-111 (2003) [Mech. Solids (Engl. Transl.) 38 (3), 78-87 (2003)].
6.  A. A. Il'yushin and B. E. Pobedrya, Fundamentals of the Mathematical Theory of Thermoviscoelasticity (Nauka, Moscow, 1970) [in Russian].
7.  Ya. S. Ufland, Integral Transforms in Elasticity Problems (Nauka, Leningrad, 1967) [in Russian].
8.  D. S. Malkus, "Finite Element Displacement Model Valid for Any Value of the Compressibility," Int. J. Solids Struct. 12 (11), 731-738 (1976).
Received 27 June 2007
Link to Fulltext
<< Previous article | Volume 42, Issue 6 / 2007 | Next article >>
Orphus SystemIf you find a misprint on a webpage, please help us correct it promptly - just highlight and press Ctrl+Enter

101 Vernadsky Avenue, Bldg 1, Room 246, 119526 Moscow, Russia (+7 495) 434-3538
Founders: Russian Academy of Sciences, Branch of Power Industry, Machine Building, Mechanics and Control Processes of RAS, Ishlinsky Institute for Problems in Mechanics RAS
© Mechanics of Solids
Rambler's Top100