Large displacement analysis of sandwich plates and shells with symmetric/asymmetric lamination

• Novel zigzag function for sandwich plates/shells with symmetric/asymmetric section.
• New through-thickness distribution of transverse shear strains for sandwich section.
• Co-rotational approach for large displacement small strain nonlinear analysis.
• Proposed 2D ‘shell’ coordinate system for effective treatment of zigzag parameters.
• Examples highlight benefits of new model for symmetric/asymmetric sandwich shells.

This paper proposes a kinematic model for sandwich plates and shells, utilising a novel zigzag function that is effective for symmetric and asymmetric cross-sections, and employing a piecewise through-thickness distribution of the transverse shear strain. The proposed model is extended to large displacement analysis using a co-rotational framework, where a 2D local shell system is proposed for the direct coupling of additional zigzag parameters. A 9-noded co-rotational shell element is developed based on the proposed approach, which utilises the MITC method for overcoming locking effects. Several linear/nonlinear analysis examples of sandwich structures demonstrate the effectiveness of the proposed approach.