Dynamic stability of sandwich cylindrical shell

• Autorzy: Romanów F. , Malinowski M.

Warianty tytułu

PL

Dynamiczna stateczność cylindrycznej powłoki warstwowej

• Języki publikacji: EN

Abstrakty

EN

In this paper a linear approach to the deflection of sandwich shells and hyperbolic state of displacement of the core as regards dynamic stability is presented. The hypothesis allows us to introduce into the calculations the actual physical and durability properties of the core and thus to treat it as an isotropic three dimension body. The method is applicable to sandwich shells having a soft core, whose characteristics take real physical values. The subject under consideration is a Iow-rise open sandwich shell loaded with forces pressing along the generating lines and simply-supported by articulation along the whole girth. It is assumed that the shell segment under consideration is symmetrical in build and consists of two isotropic flexible facings for which the Kirchhoff-Love hypothesis holds. The core is made from isotropic flexible material of densities, which are variable in the normal direction with respect to the shell surface. Solutions to the dynamic stability problem are considered within a linear approach. It is assumed that the core density variability can be described by the nonlinear continuous function. The dynamic equilibrium equation of the open sandwich shell was derived according to variational calculus on the basis of Hamilton's principle. Only inertial forces, which were normal in direction with respect to shell surface, were taken into account in kinetic energy. The constant acceleration method was applied.

PL

W pracy rozwiązano zagadnienie dynamicznej stateczności powłoki warstwowej z rdzeniem o zmiennej gęstości w kierunku poprzecznym do tworzących okładzin. Zadanie rozwiązano w ujęciu liniowym. Dla rdzenia uwzględniono trójosiowy stan przemieszczeń oraz wykorzystano nieliniową hipotezę. Jako główne kryterium wymiarowania konstrukcji przyjęto utratę stateczności, którą określono za pomocą obciążeń krytycznych. Do rozwiązania problemu wykorzystano metodę wariacyjną Hamiltona. Zadanie rozwiązano metodą numeryczną, a otrzymane wyniki podano w postaci wykresów.

Słowa kluczowe

PL

stateczność dynamiczna; powłoka cylindryczna; powłoka warstwowa

• Wydawca: Komitet Inżynierii Lądowej i Wodnej PAN ; Politechnika Warszawska, Wydział Inżynierii Lądowej
• Czasopismo: Archives of Civil Engineering
• Rocznik: 1999
• Tom: Vol. 45, nr 3
• Strony: 453--464
• Opis fizyczny: Bibliogr. 10 poz., il.

Twórcy

autor

Romanów F.

• Technical University of Zielona Góra

autor

Malinowski M.

• Technical University of Zielona Góra

Bibliografia

• 1. M. KOTEŁKO, W. WALCZAK, Stability of a sandwich cylindrical panel with discretly variable core characteristic [in Polish], 5-th Symposium - Stability of Construction, Cedzyna, Poland 1988, pp. 68-72.
• 2. J. LANGER, Dynamics of structures [in Polish], Technical University of Wrocław, Wrocław 1980.
• 3. K. MAGNUCKI, Nonlinear motion equations of conical and cylindrical sandwich panels [in Polish], Scientific Notebooks, Technical University of Poznań, No. 28, Mechanic, 1984, pp. 97-123.
• 4. M. MALINOWSKI, The elastic stability of sandwich plates and shells with variable core density in cross direction, dissertation thesis in reviewing [in Polish], Technical University of Zielona Góra, Grants sponsored by State Committee for Scientific Research, Sandwich Construction in Building of Vehicles, No. 9560404106, 1994-1996 and Nonsymetric Sandwich Construction with Variable Core Density in Automotive Vehicles, No. 9T12C03714, 1998-1999.
• 5. W. SZYC, Stability of an open sandwich cylindrical shell under dynamic compression [in Polish], Study of Engineering, 20, 4, 539-553, 1972.
• 6. FR. ROMANÓW, M. MALINOWSKI, Dynamic stability of the sandwich panel [in Polish], 8-th Symposium - Stability of Construction, Zakopane, Poland 1997.
• 7. FR. ROMANÓW, Strength of a sandwich construction [in Polish], Technical University of Zielona Góra, 1995.
• 8. WŁ. WALCZAK, M. KOTEŁKO, Influence of the variable core characteristic on the stability of the three-leyered cylindrical panel under compression [in Polish], Symposium - Model in Mechanics, Beskid Śląski, Poland 1988, pp. 543-548.
• 9. WŁ. WALCZAK, M. KOTEŁKO, Stability of rectangular panel variable stiffness of core [in Polish], Applied and Theoretical Mechanics, 22, 3-4, 363-377, 1984.
• 10. P.A. WRZECIONIARZ, Stability investigation of variable core sandwich panel, J. Engng. Mech., Proc. ASCE, 109, 6, 1983.