Analysis tools for adhesively bonded composite joints, part 2: Unified analytical theory

Adhesively bonded joints are currently of interest to the aerospace field due to the heavy reliance on bonded composite structures in new aircraft designs. In response, tools for joint analysis have been developed and examined in this two-part paper. In Part 1, a higher-order theory, considering an explicit discretization of the joint geometry, was investigated. In Part 2, a method for multiaxial stress analysis of composite joints is developed based on Mortensen's unified approach, with considerable extension to accommodate transverse in-plane strain and hygrothermal loads and most importantly, to compute the in-plane and interlambiar stresses in the adherends. Compared with other analytical methods for bonded joint analysis, the present method is capable of handling more general situations, including various joint geometries, linear and nonlinear adhesives, asymmetric and unbalanced laminates, and various loading and boundary conditions.' The method has been implemented within the commercially available HyperSizer (R) structural analysis software. Through comparison to finite element and analytical results, it is shown that the new HyperSizer joint analysis method is efficient and accurate and can serve as a capable tool for joint analysis in preliminary design, where rapid and generally accurate stress field estimates, as well as joint strengths and margins are needed.