Effect of ply thickness on damage mechanisms of composite laminates under repeated loading

Ali, H. T., Fotouhi, S. , Akrami, R., Pashmforoush, F., Pavlovic, A. and Fotouhi, M. (2020) Effect of ply thickness on damage mechanisms of composite laminates under repeated loading. FME Transactions, 48(2), pp. 287-293. (doi: 10.5937/fme2002287T)

Abstract

Barely visible impact damage (BVID) occurs in composite laminates subjected to low-velocity impact. They can then exhibit significant effect on mechanical performance of laminates. Previously, it is shown, analytically and experimentally, that BVID occurs at a critical energy level and below this energy level there is no induced damage. However, repeated impact may cause BVID even below the critical energy level. This paper is a novel investigation that deals with the cyclic behaviour of quasi-isotropic glass/epoxy laminated composites under indentation, which is a quasistatic version of low-velocity impact. In particular, this study aims to investigate the ply thickness effect on matrix crack-induced delamination damage in the case of laminated composites under cyclic quasi static indentation loadings. The effect of different parameters, such as load level and ply thickness, on the damage evolution were here investigated. Tests were performed according to the ASTM 7136 standard. Since the glass layer was translucent, it was also possible to visually inspect the matrix delamination during the tests. The laminates were subjected to load levels lower than the critical load level, while there was no evidence of damages when samples were indented just once. However, by increasing the number of cycles, matrix crack-induced delamination appeared in the samples. In brief, it was observed that the ply thickness and energy level have significant effects on the intensity of the induced damage.

• Item Type: Articles
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Fotouhi, Dr Sakineh and Fotouhi, Dr Mohammad
• Authors: Ali, H. T., Fotouhi, S., Akrami, R., Pashmforoush, F., Pavlovic, A., and Fotouhi, M.
• Subjects: T Technology > TA Engineering (General). Civil engineering (General); T Technology > TJ Mechanical engineering and machinery
• College/School: College of Science and Engineering > School of Engineering > Autonomous Systems and Connectivity; College of Science and Engineering > School of Engineering > Systems Power and Energy
• Journal Name: FME Transactions
• Publisher: University of Belgrade Faculty of Mechanical Engineering
• ISSN: 1451-2092
• ISSN (Online): 2406-128X
• Copyright Holders: Copyright © 2020 Faculty of Mechanical Engineering, Belgrade
• First Published: First published in FME Transactions 48(2): 287-293
• Publisher Policy: Reproduced under a Creative Commons License