Shear Buckling Analysis of Sandwich laminate with a Flexible Core Using a Higher-Order Theory and the Galerkin Method

Khodamorady, Mohammad Kaem; Malekade Fard, Keramat; Naavi, Seyd Mehdi; Sarkhosh, Reza

doi:10.22034/joae.2026.552301.1299

Shear Buckling Analysis of Sandwich laminate with a Flexible Core Using a Higher-Order Theory and the Galerkin Method

Articles in Press

Document Type : Original Article

Authors

mohammad kaem khodamorady ¹

keramat malekade fard ²

seyd mehdi naavi ³

reza sarkhosh ⁴

¹ PhD student, Aerospace Department, Structural Engineering, Malek Ashtar University, Tehran

² Professor, Department of Mechanical Engineering-Applied Design, Malek Ashtar University, Tehran, Iran

³ Associate Professor, Department of Mechanical Engineering-Applied Design, Malek Ashtar University, Tehran, Iran

⁴ Assistant Professor, Department of Aerospace Engineering, Aeronautical Structures, Shahid Sattari Aeronautical University, Tehran, Iran

10.22034/joae.2026.552301.1299

Abstract

This paper presents an analytical model to investigate the shear buckling behavior of composite sandwich panels with a transversely flexible core. The theoretical framework is based on a hybrid approach, combining an Improved High-Order Sandwich Panel Theory for the core—capable of accurately capturing complex deformations—and the First-Order Shear Deformation Theory (FSDT) for the face sheets. The system of governing differential equations is derived using the principle of minimum potential energy and is solved using the semi-analytical Galerkin method. Navier series functions are employed to satisfy the simply supported boundary conditions. The proposed model is successfully validated against data from the existing literature for both axial and shear buckling scenarios. A key finding involves the investigation of the aspect ratio's influence on the critical shear buckling load, revealing that the critical load decreases as the aspect ratio increases. Ultimately, this paper demonstrates that the presented model can accurately predict shear buckling loads and their corresponding mode shapes, highlighting the importance of utilizing higher-order theories for the analysis of panels with soft cores

Keywords

Sandwich laminate

Shear Buckling

Higher-Order Theory

Subjects