Tangent Stiffness in Space Frames

Abstract

A tangent stiffness matrix is derived for the geometrically nonlinear analysis of elastic space frames, based on the assumption of small relative deformations but large rotations. The approach used does not require any approximations beyond those embodied in the conventional beam-column theory, and is accordingly believed to be highly accurate. Also, a procedure is described for a practical and unambiguous representation of large rotations in three-dimensional space.