24 research outputs found
Flexuralātorsional behavior of thin-walled composite box beams using shear-deformable beam theory
This paper presents a flexuralātorsional analysis of thin-walled composite box beams. A general analytical model applicable to thin-walled composite box beams subjected to vertical and torsional loads is developed. This model is based on the shear-deformable beam theory, and accounts for the flexuralātorsional response of the thin-walled composites for an arbitrary laminate stacking sequence configuration, i.e. unsymmetric as well as symmetric. The governing equations are derived from the principle of the stationary value of total potential energy. Numerical results are obtained for thin-walled composites under vertical loading, addressing the effects of fiber angle and span-to-height ratio of the composite beam
Free vibration of axially loaded thin-walled composite box beams
A general analytical model applicable to flexuralātorsional coupled vibration of thin-walled composite box beams with arbitrary lay-ups under a constant axial force has been presented. This model is based on the classical lamination theory and accounts for all the structural coupling coming from the material anisotropy. Equations of motion are derived from the Hamiltonās principle. A displacement-based one-dimensional finite element model is developed to solve the problem. Numerical results are obtained for thin-walled composite box beams to investigate the effects of axial force, fiber orientation and modulus ratio on the natural frequencies, loadāfrequency interaction curves and corresponding vibration mode shapes
Geometrically nonlinear theory of thin-walled composite box beams using shear-deformable beam theory
A general geometrically nonlinear model for thin-walled composite space beams with arbitrary lay-ups under various types of loadings is presented. This model is based on the first-order shear deformable beam theory, and accounts for all the structural coupling coming from both material anisotropy and geometric nonlinearity. The nonlinear governing equations are derived and solved by means of an incremental NewtonāRaphson method. A displacement-based one-dimensional finite element model that accounts for the geometric nonlinearity in the von KĆ”rmĆ”n sense is developed. Numerical results are obtained for thin-walled composite box beams under vertical load to investigate the effects of shear deformation, geometric nonlinearity and fiber orientation on axialāflexuralātorsional response
On sixfold coupled vibrations of thin-walled composite box beams
This paper presents a general analytical model for free vibration of thin-walled composite beams with arbitrary laminate stacking sequences and studies the effects of shear deformation over the natural frequencies. This model is based on the first-order shear-deformable beam theory and accounts for all the structural coupling coming from the material anisotropy. The seven governing differential equations for coupled flexuralātorsionalāshearing vibration are derived from the Hamiltonās principle. The resulting coupling is referred to as sixfold coupled vibration. Numerical results are obtained to investigate the effects of fiber angle, span-to-height ratio, modulus ratio, and boundary conditions on the natural frequencies as well as corresponding mode shapes of thin-walled composite box beams
Geometrically nonlinear analysis of thin-walled composite box beams
A general geometrically nonlinear model for thin-walled composite space beams with arbitrary lay-ups under various types of loadings has been presented by using variational formulation based on the classical lamination theory. The nonlinear governing equations are derived and solved by means of an incremental NewtonāRaphson method. A displacement-based one-dimensional finite element model that accounts for the geometric nonlinearity in the von KĆ”rmĆ”n sense is developed. Numerical results are obtained for thin-walled composite box beam under vertical load to investigate the effect of geometric nonlinearity and address the effects of the fiber orientation, laminate stacking sequence, load parameter on axialāflexuralātorsional response
Flexuralātorsional behavior of thin-walled composite space frames
A general analytical model based on the first-order shear deformable beam theory applicable to thin-walled composite space frames with arbitrary lay-ups under external loads is presented. This model accounts for all the structural coupling coming from the material anisotropy. The seven governing equations are derived from the principle of the stationary value of total potential energy. A displacement-based one-dimensional 14 degree-of-freedom space beam model which includes the effects of shear deformation, warping is developed to solve the problem. Numerical results are obtained to investigate the effects of fiber orientation on flexuralātorsional responses of thin-walled composite space frame under vertical load
On sixfold coupled buckling of thin-walled composite beams
A general analytical model based on shear-deformable beam theory has been developed to study the flexuralātorsional coupled buckling of thin-walled composite beams with arbitrary lay-ups under axial load. This model accounts for all the structural coupling coming from the material anisotropy. The seven governing differential equations for coupled flexuralātorsionalāshearing buckling are derived. The resulting coupling is referred to as sixfold coupled buckling. Numerical results are obtained for thin-walled composite beams to investigate effects of shear deformation, fiber orientation and modulus ratio on the critical buckling loads and corresponding mode shapes
Vibration analysis of thin-walled composite beams with I-shaped cross-sections
A general analytical model applicable to the vibration analysis of thin-walled composite I-beams with arbitrary lay-ups is developed. Based on the classical lamination theory, this model has been applied to the investigation of loadāfrequency interaction curves of thin-walled composite beams under various loads. The governing differential equations are derived from the Hamiltonās principle. A finite element model with seven degrees of freedoms per node is developed to solve the problem. Numerical results are obtained for thin-walled composite I-beams under uniformly distributed load, combined axial force and bending loads. The effects of fiber orientation, location of applied load, and types of loads on the natural frequencies and loadāfrequency interaction curves as well as vibration mode shapes are parametrically studied
On triply coupled vibrations of axially loaded thin-walled composite beams
Free vibration of axially loaded thin-walled composite beams with arbitrary lay-ups is presented. This model is based on the classical lamination theory, and accounts for all the structural coupling coming from material anisotropy. Equations of motion for flexuralātorsional coupled vibration are derived from the Hamiltonās principle. The resulting coupling is referred to as triply coupled vibrations. A displacement-based one-dimensional finite element model is developed to solve the problem. Numerical results are obtained for thin-walled composite beams to investigate the effects of axial force, fiber orientation and modulus ratio on the natural frequencies, loadāfrequency interaction curves and corresponding vibration mode shapes
Vibration and buckling of thin-walled composite I-beams with arbitrary lay-ups under axial loads and end moments
A finite element model with seven degrees of freedom per node is developed to study vibration and buckling of thin-walled composite I-beams with arbitrary lay-ups under constant axial loads and equal end moments. This model is based on the classical lamination theory, and accounts for all the structural coupling coming from material anisotropy. The governing differential equations are derived from the Hamiltonās principle. Numerical results are obtained for thin-walled composite I-beams to investigate the effects of axial force, bending moment and fiber orientation on the buckling moments, natural frequencies, and corresponding vibration mode shapes as well as axial-moment-frequency interaction curves