Bimoment loads on space frame elements
Palavras-chave:
Nonuniform torsion, composite bars with variable cross sections, the BEM, torsion-related element stiffness matricesResumo
This paper presents an algorithm based on the Direct Stiffness Method to solve bars with composite
variable cross sections under nonuniform torsion. In this formulation, the primary and secondary torsion modes
are described by 2D Neumann's boundary-value problems, which are solved at the cross-section level by
employing the BEM. The torsional rotation angle along the element length is described by a set of ordinary
differential equations, which are solved by using weighted residual techniques. Herein, a nth-order polynomial is
adopted to approximate the torsion angle function. In this paper, we will especially assess the effects of external
bimoment loads on the calculation of stresses along the beam. Accuracy of the formulation is observed by
comparing results obtained with the present beam formulation and 3D solid ANSYS models.
