Numerical investigation of natural frequencies and mode shapes of air-supported structures
- Authors: Mokin N.A1, Kustov A.A1, Gandzhuntsev M.I1
- Moscow State University of Civil Engineering (National Research University)
- Issue: Vol 14, No 4 (2018)
- Pages: 337-347
- Section: Dynamics of structures and buildings
- URL: https://journals.rudn.ru/structural-mechanics/article/view/19281
- DOI: https://doi.org/10.22363/1815-5235-2018-14-4-337-347
Natural frequencies and mode shapes are important properties of engineering structures and buildings. Modal analysis of the prestressed membrane structures made of orthotropic material is described in this paper. The equation of motion of the system with finite number of degrees of freedom was given in the matrix form. Features of the modal analysis of prestressed system are described. To validate our technique, we have found in the literature and repeated the modal analysis of cylindrical membrane structure (inflated beam). In the source paper the analytical solutions for the natural frequencies were obtained for the one-dimensional (beam) model with taking into account orthotropic mechanical properties and prestress. In this paper the test case was solved for the spatial shell model using finite element analysis, realized in program software “ANSYS Mechanical”. Comparison between authors’ results and results described in reference is carried out. The possible reasons of results divergence are explained. The validated technique has been applied to modal analysis of an air-supported structure based on the rectangular plan of 20×50 m. Models with different mesh sizes were used to achieve the mesh convergence of results. Almost linear dependence between internal pressure and squares of natural frequencies has been received. This result is in the accordance with known solutions, described in the literature for isotropic membranes.
About the authors
Nikolay A MokinMoscow State University of Civil Engineering (National Research University)
Author for correspondence.
Postgraduate Student, Department of Structural and Theoretical Mechanics, Moscow State University of Civil Engineering (National Research University) (MGSU). Research interests: structural analysis of air-supported structures26 Yaroslavskoe Shosse, Moscow, 129337, Russian Federation
Alexey A KustovMoscow State University of Civil Engineering (National Research University)
Postgraduate Student, Department of Metal and Wooden Structures, Moscow State University of Civil Engineering (National Research University) (MGSU). Research interests: membrane structures made of technical coated fabric (including air-supported structures).26 Yaroslavskoe Shosse, Moscow, 129337, Russian Federation
Mikhail I GandzhuntsevMoscow State University of Civil Engineering (National Research University)
Cand. Sci. (Eng.), Associate Professor, Department of Structural and Theoretical Mechanics, Moscow State University of Civil Engineering (National Research University) (MGSU). Scientific interests: dynamics of structures, non-linear structural mechanics.26 Yaroslavskoe Shosse, Moscow, 129337, Russian Federation
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