Failure behavior of inclined thick adhesive joints with manufacturing defect

다국어 초록 (Multilingual Abstract)

In this paper, numerical model of thick adhesive inclined joints has been prepared and validated against experimental test to study the effect of manufacturing defect on the joint strength. The inclined joint was made up of two laminate webs attached to a wedge by a layer of adhesive. Tensile tests were conducted on many thick adhesive joint specimens with two different geometries. One half of the symmetric test specimen was then modeled using finite element analysis in which cohesive zone modeling (CZM) was used to simulate the initiation and propagation of joint fracture. The progressive fracture through the adhesive layer and along adhesive-laminate interface was carefully examined. Based on inspection of the experimental test specimen, potential manufacturing defect types and locations were incorporated in the finite element model. The reduction in strength due to these manufacturing defects was used to predict the most critical flaw type in thick inclined joints. The differences between the “flawless” numerical model and the experimental test specimen was explained when these manufacturing defects were incorporated. The results were found to be consistent with the experimental tests.

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