Flexural–torsional behavior of thin-walled composite box beams using shear-deformable beam theory

A Generalised Beam Theory (GBT) formulation is presented to analyse the structural behaviour of shear deformable thin-walled members with partially stiffened cross-sections located at arbitrary locations along their length. The deformation modes used in the formulation are taken as the dynamic eigenmodes of a planar frame representing the unstiffened cross-section. Constraint equations are derived and implemented in the GBT member analysis to model the influence of rigid stiffeners on the member response. The accuracy of the approach is validated against a shell finite element model developed in Abaqus. A numerical example describing the linear elastic behaviour of partially stiffened thin-walled member is provided to outline the usability and flexibility of the proposed method.

Download Full-text

Shear-deformable hybrid finite-element formulation for lateral-torsional buckling analysis of composite thin-walled members

Canadian Journal of Civil Engineering ◽

10.1139/cjce-2019-0560 ◽

2020 ◽

Author(s):

Emre Erkmen ◽

Vida Niki ◽

Ashkan Afnani

Keyword(s):

Finite Element ◽

Beam Theory ◽

Buckling Analysis ◽

Finite Element Formulation ◽

Element Formulation ◽

Lateral Torsional Buckling ◽

Torsional Buckling ◽

Hybrid Finite Element ◽

Thin Walled ◽

Shear Deformable

A shear deformable hybrid finite element formulation is developed for the lateral-torsional buckling analysis of fiber-reinforced composite thin-walled members with open cross-section. The method is developed by using the Hellinger-Reissner functional. Comparison to the displacement-based formulations the current hybrid formulation has the advantage of incorporating the shear deformation effects easily by using the strain energy of the shear stress field without modifying the basic kinematic assumptions of the thin-walled beam theory. Numerical results are validated through comparisons with results based on other formulations presented in the literature. Examples illustrate the effects of shear deformations and stacking sequence of the composite layers in predicting bucking loads.

Download Full-text

A continuum-mechanics interpretation of Reissner's non-linear shear-deformable beam theory

Mathematical and Computer Modelling of Dynamical Systems ◽

10.1080/13873954.2010.537512 ◽

2011 ◽

Vol 17 (1) ◽

pp. 19-29 ◽

Cited By ~ 24

Author(s):

Hans Irschik ◽

Johannes Gerstmayr

Keyword(s):

Continuum Mechanics ◽

Beam Theory ◽

Shear Deformable Beam ◽

Non Linear ◽

Linear Shear ◽

Shear Deformable

Download Full-text

Exact Matching Condition at a Joint of Thin-Walled Box Beams Under Out-of-Plane Bending and Torsion

Journal of Applied Mechanics ◽

10.1115/1.4006383 ◽

2012 ◽

Vol 79 (5) ◽

Cited By ~ 4

Author(s):

Soomin Choi ◽

Gang-Won Jang ◽

Yoon Young Kim

Keyword(s):

Beam Theory ◽

Matching Condition ◽

Higher Order ◽

Transformation Matrix ◽

Exact Matching ◽

Box Beam ◽

Out Of Plane ◽

Box Beams ◽

Thin Walled ◽

Plane Bending

To take into account the flexibility resulting from sectional deformations of a thin-walled box beam, higher-order beam theories considering warping and distortional degrees of freedom (DOF) in addition to the Timoshenko kinematic degrees have been developed. The objective of this study is to derive the exact matching condition consistent with a 5-DOF higher-order beam theory at a joint of thin-walled box beams under out-of-plane bending and torsion. Here we use bending deflection, bending/shear rotation, torsional rotation, warping, and distortion as the kinematic variables. Because the theory involves warping and distortion that do not produce any force/moment resultant, the joint matching condition cannot be obtained just by using the typical three equilibrium conditions. This difficulty poses considerable challenges because all elements of the 5×5 transformation matrix relating the field variables of one beam to those in another beam should be determined. The main contributions of the investigation are to propose additional necessary conditions to determine the matrix and to derive it exactly. The validity of the derived joint matching transformation matrix is demonstrated by showing good agreement between the shell finite element results and those obtained by the present box beam analysis in various angle box beams.

Download Full-text