Geometrically nonlinear analysis of layered beams using symbolic approach

This study presents a novel layered spatial beam model with discrete connections between layers, developed to accurately capture large displacements and rotations as well as finite strains. The formulation is characterized by simplicity, robustness and compatibility with automatic code generation, making it suitable for various applications. Key features of the model include the use of a piecewise constant strain field, the inclusion of discrete unknowns such as strains and stress resultants, and the efficient numerical implementation using the automatic code generation. The discrete connections between the layers of the model enable an efficient description of the interlaminar behaviour and the consideration of nonlinear constitutive properties. Numerical examples demonstrate the effectiveness and accuracy of the proposed approach and illustrate its potential for practical engineering applications.