Nonlinear bending analysis of anisotropic laminated tubular beams based on higher-order theory subjected to different kinds of distributed loads

Pipelines, and more generally long tubular structures, are major oil and gas industry tools used in exploration, drilling, production, and transmission. Technical challenges of the field have spawned significant research and development efforts in the mechanical behavior and the modes of failure of long tubes and pipes under various loads. Nonlinear bending analysis of anisotropic laminated composite tubular beams with different kinds of distributed loads resting on a two-parameter elastic foundation is investigated. Based on Hamilton's principle and the displacement field by Laurent series expansion form with a von Kármán-type of kinematic nonlinearity, the governing differential equations are obtained. Composite tubular beams with clamped-clamped, clamped-hinged, and hinged-hinged boundary conditions including two kinds of end conditions, namely movable and immovable are considered. A numerical solution of the transverse deflection of tubular beams by using Galerkin's method is employed to determine the relations between distributed loads and deflections of a composite beam with or without initial axial loads. The results of the present formulation concern the large-deflection bending behavior of laminated beams with different geometric and material parameters, distributed loads, end conditions and effect on elastic foundation, the obtained numerical results are also compared with the results of nonlinear finite element method. Some new results for anisotropic laminated tubular beams, such as effects of the end conditions, load characteristics and foundation stiffness are obtained for future references in the design of the civil, mechanical, aeronautical and aerospace industries.