## On a mathematical model of a bar with variable rectangular cross-section

• Generalizing an idea of I. Vekua [1] who, in order to construct theory of plates and shells, fields of displacements, strains and stresses of threedimensional theory of linear elasticity expands into the orthogonal Fourier-series by Legendre Polynomials with respect to the variable along thickness, and then leaves only first N + 1, N = 0, 1, ..., terms, in the bar model under consideration all above quantities have been expanded into orthogonal double Fourier-series by Legendre Polynomials with respect to the variables along thickness, and width of the bar, and then first (Nsub(3) + 1)(Nsub(2) + 1), Nsub(3), Nsub(2) = 0, 1,..., terms have been left. This case will be called (Nsub(3), Nsub(2)) approximation. Both in general (Nsub(3), Nsub(2)) and in particular (0,0) (1,0) cases of approximation, the question of wellposedness of initial and boundary value problems, existence and uniqueness of solutions have been investigated. The cases when variable cross-section turns into segments of straight line, and points have been alsoGeneralizing an idea of I. Vekua [1] who, in order to construct theory of plates and shells, fields of displacements, strains and stresses of threedimensional theory of linear elasticity expands into the orthogonal Fourier-series by Legendre Polynomials with respect to the variable along thickness, and then leaves only first N + 1, N = 0, 1, ..., terms, in the bar model under consideration all above quantities have been expanded into orthogonal double Fourier-series by Legendre Polynomials with respect to the variables along thickness, and width of the bar, and then first (Nsub(3) + 1)(Nsub(2) + 1), Nsub(3), Nsub(2) = 0, 1,..., terms have been left. This case will be called (Nsub(3), Nsub(2)) approximation. Both in general (Nsub(3), Nsub(2)) and in particular (0,0) (1,0) cases of approximation, the question of wellposedness of initial and boundary value problems, existence and uniqueness of solutions have been investigated. The cases when variable cross-section turns into segments of straight line, and points have been also considered. Such bars will be called cusped bars (see also [2]).

### Additional Services

Author: George Jaiani urn:nbn:de:kobv:517-opus-25347 Preprint ((1998) 21) Preprint English 1998 Universität Potsdam 2008/11/03 bar with variable cross-section; cusped bar; elastic bar SI 990 Mathematisch-Naturwissenschaftliche Fakultät / Institut für Mathematik 5 Naturwissenschaften und Mathematik / 51 Mathematik / 510 Mathematik Universität Potsdam / Schriftenreihen / Preprint / Universität Potsdam, Institut für Mathematik, Arbeitsgruppe Partielle Differentialgleichungen und Komplexe Analysis Universität Potsdam / Schriftenreihen / Preprint / Universität Potsdam, Institut für Mathematik, Arbeitsgruppe Partielle Differentialgleichungen und Komplexe Analysis / 1998 Keine Nutzungslizenz vergeben - es gilt das deutsche Urheberrecht Die Printversion kann in der Universitätsbibliothek Potsdam eingesehen werden: Preprint / Universität Potsdam, Institut für Mathematik, Arbeitsgruppe Partielle Differentialgleichungen und Komplexe Analysis, 1997- Die Online-Fassung wird auf der Homepage des Instituts für Mathematik veröffentlicht.