Bending-Twisting Deforming of Thin-Walled Composite Sections at Thermal-Mechanical Loading

Thin-walled composite sections with quite complicated open and closed cross-section are widely used nowadays. Internal stresses appeared at manufacturing of such sections can reach relatively high values and lead to complicated bending-twisting deformation of structural elements that has to be taken into consideration at the stage of design. The paper is devoted to studying of stress-strain state of long sections made of composites and having non-uniform cross-section. The theory of deformation of thin-walled sections with non-uniform properties over cross-section contour loaded with arbitrary system of thermal-mechanical loading based on generalized elasticity theory of thin-walled rods. System of resolving equations is obtained for determination of translations of composite contour arbitrary points at applying longitudinal stress only but distributed over countour length by arbitrary law. Quite high convergency of experimentally measured translations (difference is not more than 30%) with suggested analytical dependences allows to recommend developed approach for practical application. Conducted parametrical and experimental research allow to formulate practical recommendations for composing rational geometry and structure of sections with non-uniform parameters over contour and select proper parameters of manufacturing process. Reinforcing schemes and rational places of doublers installation are suggested, these can minimize section warping during its manufacturing.