Numerical Computation of Buckling Loads for Variable Stiffness Bars Under Thermomechanical Loading

a63edb9f-ab80-497e-bc12-5333ff78704820250714052611686naun:naunmdt@crossref.orgMDT DepositInternational Journal of Mechanics1998-444810.46300/9104http://www.naun.org/cms.action?id=2828415202541520251910.46300/9104.2025.19https://npublications.com/journals/mechanics/2025.phpNumerical Computation of Buckling Loads for Variable Stiffness Bars Under Thermomechanical LoadingOmarKikvidzeAkaki Tsereteli State University, 59 Tamar Mepe Street, 4600 GeorgiaIrakliTavadzeAkaki Tsereteli State University, 59 Tamar Mepe Street, 4600 GeorgiaThis study investigates the buckling of an elastic bar with a linearly varying rectangular cross-section under thermomechanical loading. The research focuses on such straight bars' stress-strain state and stability, addressing large displacement scenarios using a nonlinear system of ordinary differential equations. The mathematical model considers axial and transverse displacements, rotation angles, and internal force factors, creating a variable temperature field along the length of the bar. A numerical solution is obtained using MathCad’s built-in computational tools, enabling precise determination of displacement components, internal forces, and bending moments. The numerical calculation determines the value of the first critical force, which is essential for calculating the strength of the structure. The critical load is determined through numerical iteration from the compressive load.711202571120256122https://npublications.com/journals/mechanics/2025/a042003-002(2025).pdf10.46300/9104.2025.19.2https://npublications.com/journals/mechanics/2025/a042003-002(2025).pdfJaiani G. 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