Text Fixture for Double Cantilever Beam (DCB) Specimens Subjected to Uneven Bending Moments

Jon Svenninggaard, Jens Andreasen, Brian Bak, Esben Lindgaard

Research output: Contribution to conference without a publisher/journalPosterResearch


With the increased use of modern lightweight materials like layered fibre
reinforced polymers there is an inherent demand to characterize their
properties. One of the critical failure modes in layered materials is
delamination due to the low out of plane strength. To characterize the
interface strength in layered materials the cohesive law and fracture strength
must be known. Ideally the entire cohesive law is known in order to aid in the
design of components and structures.
In this work we present a novel test fixture which can be used to test DCB
specimens that are subjected to pure Uneven Bending Moments as a function
of the phase angle ranging from mode I to mode II loading including mixed
modes in-between. The test fixture utilizes an existing tensile testing machine
and can subject specimens to loads up to 350 Nm. The test fixture is compact
in size and designed using standard aluminium profiles for the main structure.
The load is transferred from the test machine to the specimen through a 2 mm
Dyneema rope. The rope is routed over a set of rollers that are positioned
according to the specified mode mixity and phase angle.
The kinematics of the test fixture has been analysed extensively as well as a
specially fabricated tool, made from two flat bars, which was fitted with strain
gauges to verify that the strain field from the pure moment application. The
analysis revealed negligible introductions of shear forces to the specimens.
Translated title of the contributionTest fikstur til dobbelt cantilever bjælke emner belastet med uens bøjemomenter
Original languageEnglish
Publication date15 Mar 2017
Publication statusPublished - 15 Mar 2017
Event16th Internal DCAMM Symposium - Middelfart, Denmark
Duration: 13 Mar 201715 Mar 2017


Conference16th Internal DCAMM Symposium
Internet address


  • technology, engineering and IT

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