The shear modulus of the adhesive layer and the failure mode of adhesive structure on single lap joint specimens under tensile tests are investigated in this paper.The aluminum-aluminum adherends are bonded by two different adhesives:polydimethylsiloxane (PDMS) and epoxy.The full deformation fields are measured using the digital image correlation (DIC) method with the images on the middle part of the adhesive layer recorded by a high resolution microscope.Then,the shear modulus values of the two adhesives are calculated with a simple pure shear strain model.A numerical model is proposed to simulate the single lap joint structure under tensile load in comparison with the experimental results.The results show that this method can successfully estimate the shear modulus of the adhesive layer.The failure behavior of epoxy adhesive/adherend interface is also analyzed and discussed.
Optical full-field measurement methods are now widely applied in various domains. In general,the displacement fields can be directly obtained from the measurement,however in mechanical analysis strain fields are preferred.To extract strain fields from noisy displacement fields is always a challenging topic.In this study,a finite element method for smoothing displacement fields and calculating strain fields is proposed.An experimental test case on a holed aluminum specimen under tension is applied to validate this method.The heterogeneous displacement fields are measured by digital image correlation(DIC).By this proposed method,the result shows that the measuring noise on experimental displacement fields can be successfully removed,and strain fields can be reconstructed in the arbitrary area.
B.Q.Guo,~(1,a)) H.M.Xie,~(1,b)) Y.J.Li,~1P.W.Chen,~2and Q.M.Zhang~2 1) AML,Department of Engineering Mechanics,Tsinghua University,Beijing 100084,China 2) State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081, China
