Prof. Wacław Olszak, PhD, DSc


Professor
1946Title of professor
Other
1954Corresponding Member of Polish Academy of Sciences
1956Member of Polish Academy of Sciences

Supervision of doctoral theses
1.1964Rychlewski Jan  Nośność graniczna powłok helikoidalnych 
2.1962Wesołowski Zbigniew  Stateczność przy niektórych przypadkach rozciągania w świetle teorii odkształceń skończonych 
3.1959Mróz Zenon  Nośność graniczna i kształtowanie wytrzymałościowe płyt i powłok 
4.1959Perzyna Piotr  Fale naprężenia w ośrodkach niesprężystych 
5.1949Ziemba Stefan  Walec kołowy pełny o skończonej długości pod działaniem sił osiowo ściskających 

Recent publications
1.Olszak W., Ostrowska-Maciejewska J., The plastic potential in the theory of anisotropic elastic-plastic solids, ENGINEERING FRACTURE MECHANICS, ISSN: 0013-7944, DOI: 10.1016/0013-7944(85)90072-4, Vol.21, No.4, pp.625-632, 1985
Abstract:

In the paper the yield condition is proposed for the most general anisotropic material. It is one of the possible generalizations of the Huber-Mises-Hencky yield condition for the case of anisotropy. The body considered is anisotropic elastically as well as plastically. It is assumed that the plastic anisotropy tensor is a definite function of the elastic anisotropy tensor. The corresponding flow function is a part of the strain energy and its value remains unchanged when all normal components of stress are increased by the same value. The theory of the eigen states for fourth order tensors is used. The plastic anisotropy tensor proposed has the same deviatoric eigen states as the elastic anisotropy tensor. The proposed yield condition reduces to that of Huber-Mises-Hencky when the anisotropy is vanishingly small. The method presented in this paper can be also applied to describe other types of plastic anisotropy tensor.

Affiliations:
Olszak W.-IPPT PAN
Ostrowska-Maciejewska J.-IPPT PAN
2.Nowacki W., Olszak W., Misztal F., Szymanowski W., Nałęcz M., Wydział IV - Nauk Technicznych w 25-leciu Polskiej Akademii Nauk, Nauka Polska, ISSN: 0028-1271, Vol.XXVI, No.5, pp.23-29, 1978
3.Bychawski Z., Olszak W., Rheological approach to crack propagation and fracture mechanisms, ENGINEERING FRACTURE MECHANICS, ISSN: 0013-7944, DOI: 10.1016/0013-7944(76)90092-8, No.8, pp.1-267, 1976
Abstract:

The paper is concerned with a nonlinear description of the kinetics of crack propagation in bodies exhibiting rheological properties. The analysis is based on the concept of a time-dependent cohesion modulus for an ageing nonlinear viscoelastic material. A simple model of an infinite thin plate with a rectilinear crack is considered. The discussion is followed by some conclusions.

Affiliations:
Bychawski Z.-IPPT PAN
Olszak W.-IPPT PAN
4.Olszak W., Perzyna P., Physical theory of viscoplasticity for small deformations, Mechanics Research Communications, ISSN: 0093-6413, DOI: 10.1016/0093-6413(74)90062-7, Vol.1, No.4, pp.187-190, 1974
5.Olszak W., Plastizitäts-und energetische Kennzeichnungskriterien für rheologisch reagierende Stoffe, ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK, ISSN: 0044-2267, DOI: 10.1002/zamm.19730531227, Vol.53, No.12, pp.T77-T77, 1973
6.Olszak W., Perzyna P., On thermal effects in viscoplasticity, ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND PHYSIK ZAMP, ISSN: 0044-2275, DOI: 10.1007/BF01590623, Vol.20, No.5, pp.676-680, 1969
7.Olszak W., Perzyna P., Les equations constitutives et phenomenes de relaxation dans les milieux elasto/visco-plastiques, Rendiconti del Seminario Matematico e Fisico di Milano, ISSN: 0370-7377, DOI: 10.1007/BF02924479, Vol.38, No.1, pp.12-18, 1968
Abstract:

The paper consists of two parts. The first part is devoted to a discussion of the constitutive equations describing the dynamic properties of soils. In the second part, the relaxation problem in an elastic/visco-plastic soil is considered.

Affiliations:
Olszak W.-IPPT PAN
Perzyna P.-IPPT PAN
8.Olszak W., Sur la théorie des phénomènes visco-plastiques, Rendiconti del Seminario Matematico e Fisico di Milano, ISSN: 0370-7377, DOI: 10.1007/BF02924478, Vol.38, pp.9-11, 1968
Abstract:

The lecture presents a synthetic survey on the theory of viscoplasticity (reflecting the rate-sensitive dynamic properties of materials). Some examples of its applications are also discussed (relaxation phenomena occurring in elastic/visco-plastic media as well as the propagation of stress waves in such continua). Besides, we generalize the existing theories by introducing a nonstationary yield condition (variable with time). Finally we propose a further generalization of the yield criterion based on the notion of the conserved (accumulated) as well as the dissipated energy.

Affiliations:
Olszak W.-IPPT PAN
9.Olszak W., Perzyna P., The constitutive equations for elastic/visco-plastic soils, Journal of Mathematical and Physical Sciences, ISSN: 0047-2557, Vol.2, pp.67-72, 1968
10.Bychawski Z., Olszak W., Energetyczna interpretacja stanów krytycznych w ciałach lepkosprężystych, Prace IPPT - IFTR Reports, ISSN: 2299-3657, No.2, pp.1-53, 1967
11.Olszak W., Rychlewski J., Urbanowski W., Plasticity Under Non-Homogeneous Conditions, Advances in Applied Mechanics, ISSN: 0065-2156, DOI: 10.1016/S0065-2156(08)70122-4, Vol.7, pp.131-214, 1962
Abstract:

The theory of plasticity represents one of the branches of rapidly developing continuum mechanics. The progress consists of both a careful analysis of the basic equations and physical relations and an extension of the range of problems and effective solutions covered by this theory. In real media the non-homogeneity of mechanical properties may be caused by numerous phenomena and its nature may be very diverse. First, it is evident that a universal property of bodies occurring in practice is their microscopic non-homogeneity. It is well- known that there have been many successful1 attempts to include microscopic non-homogeneity in the structure of Continuum Theory. The objective of the chapter, however, is the macroscopic nonhomogeneity that is taking place in regions whose linear dimensions are comparable with the characteristic dimensions of the body under consideration. The nonhomogeneity of mechanical properties may be caused, for instance, by phenomena such as the influence of flow of elementary particles, the action of temperature gradients, a nonhomogeneous hardening of the material, different types of surface working, nonhomogeneity of the composition, and so on.

Affiliations:
Olszak W.-IPPT PAN
Rychlewski J.-IPPT PAN
Urbanowski W.-IPPT PAN
12.Perzyna P., Olszak W., Propagation of spherical waves in a non-homogeneous elastic-viscoplastic medium, BULLETIN OF THE POLISH ACADEMY OF SCIENCES: TECHNICAL SCIENCES, ISSN: 0239-7528, Vol.9, pp.509-516, 1961
13.Olszak W., On some basic aspects of the theory of non-homogeneous loose and cohesive media, ARCHIWUM MECHANIKI STOSOWANEJ, ISSN: 0373-2029, No.6, pp.751, 1960
14.Olszak W., Perzyna P., Variational theorems in general viscoelasticity, Ingenieur-Archiv, ISSN: 0020-1154, DOI: 10.1007/BF00536117, Vol.28, No.1, pp.246-250, 1959
15.Olszak W., Mróz Z., Note on the completeness of elastic-plastic solution to certain boundary-value problems for the eccentric ring, ARCHIWUM MECHANIKI STOSOWANEJ, ISSN: 0373-2029, Vol.10, pp.441-444, 1958
16.Olszak W., Murzewski J., Elasto-plastische Biegung von nicht-homogenen orthotropen Kreisplatten, ZAMM-ZEITSCHRIFT FUR ANGEWANDTE MATHEMATIK UND MECHANIK, ISSN: 0044-2267, DOI: 10.1002/zamm.19570370728, Vol.37, No.7-8, pp.277-278, 1957
17.Olszak W., Mróz Z., Elastic bending of circular plates with eccentric holes /application of the method of inversion/, ARCHIWUM MECHANIKI STOSOWANEJ, ISSN: 0373-2029, Vol.9, No.125, pp.153, 1957
18.Olszak W., Urbanowski W., The plastic potential and the generalized distorsion energy in the theory of non-homogeneous anisotropic elastic-plastic bodies, ARCHIWUM MECHANIKI STOSOWANEJ, ISSN: 0373-2029, Vol.8, No.4, pp.671-694, 1956
19.Mutermilch J., Nowacki W., Olszak W., Dziesięciolecie rozwoju konstrukcji inżynierskich w Polsce Ludowej, INŻYNIERIA I BUDOWNICTWO, ISSN: 0021-0315, Vol.11, No.7, pp.198-201, 1954

Conference papers
1.Olszak W., Perzyna P., On elastic/visco-plastic soils, IUTAM Symposia, Rheology and Soil Mechanics / Rhéologie et Mécanique des Sols, 1964-04-01/04-08, Grenoble (FR), pp.47-57, 1966
2.Olszak W., Perzyna P., The constitutive equations of the flow theory for a non-stationary yield condition, 11th International Congress of Applied Mechanics, 1964-08-30/09-05, Munich (DE), pp.545-553, 1964