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The objective of this paper is to investigate the performance of adhesive joints of carbon/epoxy wind turbine blade subjected to combined bending and tension loadings through finite element method. The influence of adhesive material properties and geometrical details including fillet and imperfections was examined in terms of interlaminar stresses in the adhesive layer. The variation of stress intensity with change in adhesive shear modulus has also been investigated, while contour integral method was used for evaluating the stress intensity factors (SIF) at the imperfection tip. Furthermore, the strength of the joint was assessed through the crack initiation and propagation analysis. Results suggested that either adding a fillet or considering the plasticity led to the reduced peak stresses at the edge of the adhesive layer and redistributed the load to low stress regions. Inclusion of imperfections has resulted in high stress concentrations in the adhesive layer and reduction in the strength of the joint. Compared to the filleted adhesive, the strength of the joint reduced 2.4% and 4.8% considering a flat adhesive and filleted adhesive with throughthickness imperfection, respectively. Large shear modulus of the adhesive diminishes the fracture strength with the increased SIF.

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Efficiency of post-operative sutured tissues depends on the state stress and strain, affecting the rate of wound healing. The objective of this study was to examine, the effect of suture size and stiffness, on the deformation of an incised continuous tissue. A simple running suture configuration was modeled and analyzed using 3D Finite Element Method (FEM). Prolene suture thread (Ethicon Inc.) of size 7-0 and 8-0 with varying material stiffness in the range of 6240 MPa to 30 MPa have been used whereas CryoValve aorta graft (Cryo Life Inc.) is considered as tissue material. Results show that the suture size has major impact on the deformation state of the tissue than the suture stiffness. Even though the difference in material stiffness caused a negligible change in strain, there is 55% increase in max principal strain away from suture line. Moreover, altering the suture size from 7-0 to 8-0 resulted in a 12% reduction in max tissue stresses. Because of the localization of max stress around the corner holes of the flaw, there is a fair chance of damage initiation at this location.