Measuring Cohesive Laws for Interfaces in Sandwich Structures

Christian Lundsgaard-Larsen, Bent F. Sørensen, Carl Christian Berggreen, Rasmus Christian Østergaard

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review


Extraction of cohesive laws are conducted for interfaces in sandwich structures. Separation between face and core are driven by pure bending moments applied to double cantilever beam (DCB) specimens. By varying the ratio between moments applied to the beams the test is conducted for different mode mixities. The sandwich specimens consists of glass fiber faces and Divinycell H200 foam core with a pre-crack between face and core made with teflon film. Arbitrary stiffening of the sandwich faces with steel bars adhered to the faces reduces rotations and ensures that the method is useable for a wide range of materials. The J integral is employed in closed form and the opening of the pre-crack tip is recorded by a commercial optical measurement system. Cohesive laws are extracted by differentiating J with respect to the normal and tangential opening of the pre-crack tip. Results for one specimen are presented and discussed.
Original languageEnglish
Title of host publicationPolymer Composite Materials for Wind Power Turbines
EditorsH. Lilholt, B. Madsen, T.L. Andersen, L.P. Mikkelsen, A. Thygesen
Number of pages375
Place of PublicationRoskilde, Denmark
PublisherRisø National Laboratory
Publication date2006
ISBN (Print)87-550-3528-0
Publication statusPublished - 2006
Event27th Risoe International Symposium on Materials Science - Risø, Denmark
Duration: 4 Sep 20067 Sep 2006


Conference27th Risoe International Symposium on Materials Science


Dive into the research topics of 'Measuring Cohesive Laws for Interfaces in Sandwich Structures'. Together they form a unique fingerprint.

Cite this