An alternative formulation of geometrical （另一种几何公式）.pdfVIP

Recent Advances in Engineering Mechanics, Structures and Urban Planning An alternative formulation of geometrical stiffness matrix for thin- walled I-beam element Shyh-Rong KUO Department of Harbor and River Engineering, National Taiwan Ocean University, Keelung 20224, TAIWAN srkuo@ntou.mail.edu.tw J.D. Yau Department of Architecture Tamkang University No.151, Yingzhuan Rd., Tamsui Dist., New Taipei City 25137 TAIWAN Abstract: - To simplify laborious procedure in formulating geometric stiffness matrix of thin-walled beam element, this study decomposes an I-beam element into three narrow beam components in conjunction with geometrical hypothesis of rigid cross section. First the Yang et al.’s simplified geometric stiffness matrix [k ] of a rigid beam element was applied to the basis of geometric stiffness of a narrow beam element. So g 12x 12 we can use rigid beam assemblage and stiffness transformation procedure to derivate the geometric stiffness matrix [k ] of an I-beam element. It is emphasized that the nodal warping deformations are included. From g 14x 14 the derived [k ] matrix, it can take into account the nature of various rotational moments, such as semi- g 14x 14 tangential (ST) property for St. Venant torque and quasi-tangential (QT) propert