Cover
Vol. 25 No. 2 (2025)

Published: December 31, 2025

Pages: 30-37

Original Article

Determination of the Stress Intensity Factor in a Sandwich Structure with a Hexagonal Core under Various Loading Conditions

Esraa Sabih Talib 1 Rafil Mahmood lafta 1
1 Department of Mechanical Engineering, College of Engineering, University of Basrah, Basrah, Iraq
History
  • Received: April 3, 2025
  • Revised: June 12, 2025
  • Accepted: June 21, 2025
  • Available Online: December 31, 2025
DOI

https://doi.org/10.33971/bjes.25.2.4

Abstract

Due to the significance of structural sandwiches with hexagonal cores, utilized in various applications including aerospace, marine industries, and rail transport, and their design that imparts superior strength compared to conventional forms. In this paper, fracture behavior of these structural sandwiches was examined. Initially, the equivalent modulus of elasticity was empirically determined for many cell side lengths, utilizing the stress-strain relationship derived from tensile tests on hexagonal specimens. The fracture behavior was analyzed numerically using Abaqus software. The core and the complete sandwich structure were examined under various loads, including tensile and shear forces. The influence of the hexagonal cell dimensions on the fracture modules and the stress intensity factor (SIF), was assessed. It was observed that when the cell thickness remains constant while the side length varies, the SIF increases with the increasing in side length. This leads to the influence of stiffness, where it decreases with the increase in side length of the cell core. For instance, when the side length is 10, the stress intensity factor is 4.821, while when the side length is 20, the stress intensity factor becomes 22.35. A relationship was found between the stress intensity factor and thickness, similar to the tension case. However, here, a relationship between (kl) and the (a/tc) ratio was established.

Keywords

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