Analysis of two box beams-joint systems under in-plane bending and axial loads by one-dimensional higher-order beam theory. (July 2016)

• Record Type: Journal Article
• Authors: Choi, Soomin; Kim, Yoon Young
• Is Part Of: International journal of solids and structures. Volume 90(2016)
• Page Start: 69
• Page End: 94
• Publication Date: 2016-07
• Subjects: Thin-walled box beam -- Higher-order beam theory -- Bending warping -- Bending distortion -- Joint matching conditions; Mechanics, Applied -- Periodicals; Structural analysis (Engineering) -- Periodicals; Elastic solids -- Periodicals; Mécanique appliquée -- Périodiques; Constructions, Théorie des -- Périodiques; Solides élastiques -- Périodiques; Elastic solids; Mechanics, Applied; Structural analysis (Engineering); Periodicals; 624.18
• DOI: 10.1016/j.ijsolstr.2016.04.009
• Languages: English
• ISSNs: 0020-7683

Abstract

Highlights: Two box beams-joint systems are analyzed by one-dimensional beam theory. The beam systems are subjected to in-plane loads. Higher-order deformation (bending warping and distortion) degrees are considered. Exact matching conditions at a joint of two box beams are newly derived. The proposed approach effectively handles arbitrarily-angled box beam systems. Abstract: If two thin-walled box beams meet at a joint, significant flexibilities that cannot be dealt with by the classical Euler or Timoshenko beam theory are observed. Especially under in-plane bending and axial loads, the deformation of the two box beams-joint system near the joint region is so complicated that no theoretical one-dimensional approach that interprets its mechanical behavior correctly has yet been proposed. To establish an effective higher-order beam theory, we introduce a new additional bending distortion degree representing anticlastic curvature effects and also redefine the section-shape functions of the bending warping and bending distortion degrees. In box beams-joint systems, it is crucial to find the matching conditions among field variables at the joint, but no exact conditions applicable for the systems under in-plane bending and axial loads are available. In this paper, we newly derive the explicit form of the transformation matrix relating six field variables of two box beams at a joint–axial displacement, transverse displacement, in-plane bending/shear rotation, bending warping, and two bending distortions. The accuracy and validity of the developed higher-order beam theory and the exact matching conditions are checked by comparing the present beam based results and ABAQUS shell analysis results for various box beams with different joint angles.