RUDN Journal of Engineering ResearchRUDN Journal of Engineering Research2312-81432312-8151Peoples’ Friendship University of Russia1891610.22363/2312-8143-2018-19-2-203-213Research ArticleNUMERICAL MODELING OF THE BUCKLING RESISTANCE OF RULED HELICOIDAL SHELLSGiloulbeMathieu<p>PhD civil engineering, Associate Professor, Department of architecture and civil engineering, Engineering Academy, RUDN University. Research interests: theory of thin elastic shells, nonlinear stability of shells of complex geometry, computer modeling</p>giloulbem@hotmail.comMarkovichAleksei S<p>PhD civil engineering, Associate Professor, Department of architecture and civil engineering, Engineering Academy, RUDN University. Research interests: construction mechanics, numerical methods for calculating structures, computer modeling.</p>markovich.rudn@gmail.comTupikovaEvgeniya M<p>PhD civil engineering, Assistant Professor, Department of architecture and civil engineering, Engineering Academy, RUDN University. Research interests: theory of thin elastic shells, nonlinear stability of shells of complex geometry, computer modeling</p>tupikova_em@rudn.universityZhurbinYulian V<p>Graduated from the Peoples’ Friendship University of Russia in 2016 with a degree in “Construction Engineering and Technology”. Currently studying in full-time magistracy in the specialty “Theory and design of buildings and structures”. Research interests: computer modeling and analysis of building structures</p>julianzhurbin2015@gmail.comPeoples’ Friendship University of Russia (RUDN University)1512201819220321319072018Copyright © 2018, Giloulbe M., Markovich A.S., Tupikova E.M., Zhurbin Y.V.2018<p>The paper concerns the buckling analysis of thin shells of right helicoid form. The buckling analysis was performed by the means of finite element software. Shells with variable pitch number and same contour radiuses and height were compared, their straight edges fixed and the curvilinear contours free. Was used for the analysis triangular shell finite elements (No. 42). The total number of nodal unknowns was the same in each of the considered tasks and was 16 206. Numerical investigation of the stability was performed by the finite element method in the software package Lira-Sapr 2017. The number of nodes in each task was the same. The loading includes combination of gravity (dead load) and vertical equally distributed load. The buckling mode and stability factor for every case is calculated. Boundary conditions - elastic built in shells along the bottom and top generatrices. To plot the midsurface of each shell were used parametric equations in rectangular coordinates. Of particular interest is the study of natural oscillations of the shells considered. 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