The direct force correction based framework for general co-rotational analysis
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The use of nonlinear projection matrix in co-rotational (CR) analysis was pioneered by Rankin and Nour-Omid in 1990s (Computers Structures, 30 (1988) 257-267; Comput. Methods Appl. Mech. Engrg., 93 (1991) 353-384), and has almost became a standard manner for CR formulations deduction over the past thirty years. This matrix however relies heavily on a hysterical and sophisticated derivation of the variation of the local displacements to the global ones, leading to complicated expressions for the internal force vector and the tangent stiffness matrix, which may devalue the simplicity and convenience for the original intention of using CR approach. This paper begins by making a discussion on existing element independent CR formulation and the objective is to develop a new and simple framework for general CR analysis that avoids using conventional nonlinear projection matrix. Multiple numerical examples involving various kinds of elements and different choices of element local CR frame are presented to demonstrate the performance of the proposed framework. The outcomes show that for all the examples the accuracy of the results are comparable with those obtained in conjunction with conventional nonlinear projection matrix.
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