Analysis of Bonded Joints.
NATIONAL AERONAUTICS AND SPACE ADMINISTRATION HAMPTON VA LANGLEY RESEARCH CEN TER
Pagination or Media Count:
A refined elastic analysis of bonded joints which accounts for transverse shear deformation and transverse normal stress was developed to obtain the stresses and displacements in the adherends and in the bond. The displacements were expanded in terms of polynomials in the thicknesswise coordinate the coefficients of these polynomials were functions of the axial coordinate. The stress distribution was obtained in terms of these coefficients by using strain-displacement and stress-strain relations. The governing differential equations were obtained by integrating the equations of equilibrium. These differential equations were solved, and the boundary conditions interface or support were satisfied to complete the analysis. Single-lap, flush, and double-lap joints were analyzed. The effects of adhesive properties, plate thicknesses, material properties, and plate taper on maximum peel and shear stresses in the bond were studied. Also, the results obtained by using the thin-beam analysis available in the literature were compared with the results obtained by using the refined analysis. In general, thin-beam analysis yielded reasonably accurate results, but in certain cases the errors were high. Numerical investigations showed that the maximum peel and shear stresses in the bond can be reduced by 1 using a combination of flexible and stiff bonds, 2 using stiffer lap plates, and 3 tapering the plates. Of the three joints considered, for a given total adhesive thickness and joint volume, the double-lap joint had the smallest maximum peel and shear stresses in the bond, whereas the flush joint had the highest. MM
- Adhesives, Seals and Binders
- Couplers, Fasteners and Joints