Interfacial Crack Arrest in Sandwich Panels with Embedded Crack Stoppers Subjected to Fatigue Loading
- 204 Downloads
A novel crack arresting device has been implemented in sandwich panels and tested using a special rig to apply out-of-plane loading on the sandwich panel face-sheets. Fatigue crack propagation was induced in the face-core interface of the sandwich panels which met the crack arrester. The effect of the embedded crack arresters was evaluated in terms of the achieved enhancement of the damage tolerance of the tested sandwich panels. A finite element (FE) model of the experimental setup was used for predicting propagation rates and direction of the crack growth. The FE simulation was based on the adoption of linear fracture mechanics and a fatigue propagation law (i.e. Paris law) to predict the residual fatigue life-time and behaviour of the test specimens. Finally, a comparison between the experimental results and the numerical simulations was made to validate the numerical predictions as well as the overall performance of the crack arresters.
KeywordsSandwich structures Composites Finite element analysis Fracture mechanics Fatigue
The work was sponsored by the Danish Council for Independent Research | Technology & Production Sciences (FTP) under the research grant “Enhanced Performance of Sandwich Structures by Improved Damage Tolerance” (SANTOL) (Grant 10082020). The Divinycell H100 material used in this study was provided for free by DIAB A/S. The work has been conducted in collaboration with and co-sponsored by the Technical University of Denmark, Aalborg University, Denmark, the University of Southampton, UK, Siemens Wind Power A/S, Denmark, and LM Wind Power Blades A/S, Denmark.
- 1.Zenkert D.: An introduction to sandwich construction. Chameleon Press Ltd, London (1995)Google Scholar
- 2.Shenoi, R.A, Groves, A, Rajapaske, Y.D.S.: (2005) Theory and Applications of Sandwich Structures, University of Southampton RGSE, ISBN-13: 978–0854328253Google Scholar
- 4.Dundurs, J.: Edge-bonded dissimilar orthogonal elastic wedges. J. Appl. Mech, 36:650–652 (1969)Google Scholar
- 14.Moslemian, R., Berggreen, C., & Karlsson, A. M.: (2010) Application of a Cycle Jump Technique for Acceleration of Fatigue Crack Growth Simulation. In Proceedings — NAFEMS Nordic Seminar: Simulating Composite Materials and Structures
- 15.Moslemian, R., Berggreen, C., Quispitupa, A., & Hayman, B.: (2010) Damage assessment of compression loaded debond damaged sandwich panels. In G. Ravichandran (Ed.), ICSS 9
- 17.Hirose, Y., Matsubara, G., Hojo, M., Matsuda, H., Inamura, F.: (2008) Evaluation of modified crack arrester by fracture toughness tests under mode I type and mode II type loading for foam core sandwich panel. In: Proc. US-Japan conference on composite materials 2008, Tokyo, JapanGoogle Scholar
- 21.Bozhevolnaya, E, Jakobsen, J & Thomsen, O.: Fatigue Performance of Sandwich Beams With Peel Stoppers, 45:349–357 (2009)Google Scholar
- 22.Bozhevolnaya E., Jakobsen J., Thomsen O.T.: Performance of sandwich panels with peel stoppers, strain. Int J Exp Mech. 45, 349–357 (2009)Google Scholar
- 27.Martakos, G., Andreasen J. H., Berggreen C., Thomsen O. T.: (2016) Experimental Investigation of Interfacial Crack Arrest in Sandwich Beams Subjected to Fatigue Loading using a Novel Crack Arresting Device. Submitted for publication.Google Scholar
- 28.Martakos, G., Andreasen J. H., Berggreen C., Thomsen O. T.: (2016) Interfacial Crack Arrest in Sandwich Beams Subjected to Fatigue Loading using a Novel Crack Arresting Device - Numerical modelling. Submitted for publication.Google Scholar
- 29.DIAB. Divinycell H-Grade Technical data, Laholm (Sweeden), 2014. (http://www.diabgroup.com).
- 30.ANSYS® (2013) Academic Research, Release 15.0Google Scholar
- 31.Paris, P., Erdogan, F.: A critical analysis of crack propagation laws, J Basic Engng Trans ASME Ser D, 85:528–534 (1963)Google Scholar
- 32.Manca, M., Berggreen, C., Carlsson, L. A.: G-control fatigue testing for cyclic crack propagation in composite structures. Eng Fract Mech (2015)Google Scholar