Fracture characterization of sandwich structures interfaces under mode I loading

• Type: Article in International Scientific Journal
• Date: 2010

Authors

Ramantani, DA (Author) Other; de Moura, MFSF (Author) FEUP; Campilho, RDSG (Author) Other; Marques, AT (Author) FEUP

Journal

Title: Composites Science and Technology

Vol. 70

Pages: 1386-1394

ISSN: 0266-3538

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 23 Citations

ISI Web of Science

Scopus - 28 Citations

Scientific classification

FOS: Engineering and technology > Materials engineering

Other information

Authenticus ID: P-003-36J

DOI: 10.1016/j.compscitech.2010.04.018

Abstract (EN): The accurate prediction of failure of sandwich structures using cohesive mixed-mode damage models depends on the accurate characterization of the cohesive laws under pure mode loading. In this work, a numerical and experimental study on the asymmetric double cantilever beam (DCB) sandwich specimen is presented with the objective to characterize the debonding fracture between the face sheet and the core under pure mode I. A data reduction method based on beam theory was formulated in such a way to incorporate the complex damaging phenomena of the debonding due to the material and geometric asymmetry of the specimen, via the consideration of an equivalent crack length (a(e)). Experimental DCB tests were performed and the proposed methodology was followed to obtain the debonding fracture energy (G(lc)). The experimental tests were numerically simulated and a cohesive damage model was employed to reproduce crack propagation. An inverse method was followed to obtain the local cohesive strength (sigma(u,l)) based on the fitting of the numerical and experimental load-displacement curves. With the value of fracture energy and cohesive strength defined, the cohesive law for interface mode I fracture is characterized. Good agreement between the numerical and the experimental R-curves validates the accuracy of the proposed data reduction procedure.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 9