Print Email Facebook Twitter On cohesive element parameters and delamination modelling Title On cohesive element parameters and delamination modelling Author Lu, X. (National University of Singapore) Ridha, M. (National University of Singapore) Chen, B. Y. (TU Delft Aerospace Structures & Computational Mechanics) Tan, V. B.C. (National University of Singapore) Tay, T. E. (National University of Singapore) Date 2019 Abstract The cohesive element (CE) has been widely used to model delamination in laminated composites. The penalty stiffness, interfacial strength and fracture toughness are three CE parameters that often determine the accuracy of the numerical analysis by finite elements (FEs). The fracture toughness may be experimentally determined through standard fracture tests. The interfacial strength is difficult to obtain experimentally but also plays a crucial role in predictive numerical modelling. The penalty stiffness is a numerical parameter whose range of values may influence computational results. Recently, the CE has been deployed to model the initiation and propagation of delamination in composite structures where no pre-existing cracks or delamination has been assumed. The parameters are often calibrated, but comprehensive studies on the influence of CE parameters and their selection criteria remain limited in the literature. In the present paper, the effects of CE parameters on delamination modelling are systematically examined. The sensitivity of the overall progressive damage process and failure load to the assumed CE strengths and stiffness is studied based on selected examples of fracture and coupon-level tests. With varying CE strengths employed in the FE analyses, two distinct kinds of failure behaviour, namely the strength-sensitive and strength-insensitive delamination processes, have been observed, depending on the geometry and ply layups of composite materials. On the other hand, the penalty stiffness of CE mainly affects the computational efficiency and accuracy of delamination modelling. The failure mechanisms and physics behind are investigated to get better understanding on the numerical effects of CE parameters, and thus provide the selection guidelines in practical analyses. Subject A. Cohesive elementB. DelaminationC. Finite element methodD. Composite laminates To reference this document use: http://resolver.tudelft.nl/uuid:7f03dde7-f8ed-4ca8-8ed4-76f24b8286e7 DOI https://doi.org/10.1016/j.engfracmech.2018.12.009 Embargo date 2021-12-17 ISSN 0013-7944 Source Engineering Fracture Mechanics, 206, 278-296 Bibliographical note Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public. Part of collection Institutional Repository Document type journal article Rights © 2019 X. Lu, M. Ridha, B. Y. Chen, V. B.C. Tan, T. E. Tay Files PDF 1_s2.0_S0013794418308609_main_1.pdf 2.07 MB Close viewer /islandora/object/uuid:7f03dde7-f8ed-4ca8-8ed4-76f24b8286e7/datastream/OBJ/view