Efficient analysis of stress concentrations in laminated composite structures with geometric discontinuities

Abstract

A semi-analytical analysis method for displacements, strains and stresses in laminated composite plates with local reinforcement by patches/doublers is presented. The analysis approach is based on a "global" solution provided by the Classical Laminate Plate Theory (CLPT). Further, a "local" model is introduced which discretizes each laminate ply into several mathematical layers. For each of these mathematical layers an additional displacement field is postulated. These additional displacement fields capture the localized phenomena close to the free edge of the patch and in the plate-doubler junction but decay rapidly with increasing distance from these locations, i.e. the CLPT solution is recovered. The model shows excellent agreement with FE analyses for different plate-doubler lay-ups with the benefit of highly reduced computational costs.