For making rivet and bolt connections, making a hole is necessary. While basic S-N graph can be extracted from design documents, analysis of stress can be used for two different approaches. The first approach is the theoretical derivation of analytical relations with simplified assumptions like planar stress or uniform bolt load distribution. The other one is the numerical simulation using robust codes like Abaqus software. By using these two approaches, residual stress distribution around the hole can be extracted in various conditions. In this experiment, an aluminium 2024-T3 plate with 3.2 mm thickness is considered. The stress analysis results and basic S-N graph were combined and discursive S-N graphs were obtained for different cold-expanded bolted holes. These graphs were compared with experimental data in several steps. First, the bolt fastening was considered. In the second step, cold expansion was considered and in the final step, the effects of fastening bolts and nuts and cold expansion was considered simultaneously. At last, a comparison between various steps was drawn. The results of this study showed that this new analytical method on distribution of residual stresses around cold expansion holes is as effectiveness as old methods. Manuscript profile

In this paper, Asymmetric buckling analysis of functionally graded (FG) Circular plates with temperature dependent property that subjected to the uniform radial compression and thermal loading is investigated. This plate is on an elastic medium that simulated by Winkler and Pasternak foundation. Mechanical properties of the plate are assumed to vary nonlinearly by temperature change. The equilibrium equations are obtained using the classical plate theory (CPT), Von Karman geometric nonlinearity and virtual displacement method. Existence of bifurcation buckling is examined and stability equations are obtained by means of the adjacent equilibrium criterion. The effects of elastic foundation coefficient, thickness to radius, power law index, and temperature-dependency of the material properties on critical buckling load of FG plates are presented. The results of the present work have been compared with the results of other investigator and the results of the comparison are very good. It is found that by increasing temperature, critical buckling load decreases. It is also concluded that the critical buckling load of (FG) Circular plates increases with an increase in the Winkler and Pasternak constants of elastic foundation. Manuscript profile