Search

Buckling of steel thin-walled semi-spherical shells with square cutout due to axial compressive loads has been studied by numerical simulations, and results were compared with those from the experiments. Three vertical compression loadings were applied to specimens using the following methods: a rigid flat plate and a rigid bar with circular and spherical cross sections. The main aim of this study is to determine the influence of the cut out size-to-location (a/H) and the thickness-todiameter (t/D) on the mean collapse load of the semi-spherical shells. The finite element models were analyzed using ABAQUS nonlinear buckling analysis and the experimental tests were performed using an INSTRON 8802 servo-hydraulic machine. Finally, the different results obtained using the two analysis methods were compared. The comparison reveals that experimental and numerical nonlinear model results match closely with each other. [ABSTRACT FROM AUTHOR]

Conical shells are extensively used in numerous types of engineering structures with various types of geometric imperfections. Nonetheless, quite few are the studies investigating the effect of special types of imperfections on the buckling load of conical shells under external pressure. In the present study, depression type of imperfection which is found in the zone of longitudinal weld is in the center of attention. To this end, this paper reports on different simulations including finite element results and discusses the effect of this type of imperfection on the critical buckling load of such structures. Obtained results are compared with the previous corresponding test results, some theoretical predictions, recommendations and codes. [ABSTRACT FROM AUTHOR]

Three-dimensional finite element analysis is applied to verify mechanical behavior of spot welds for one, three and five spot welds under tensile and compressive loading conditions. The elastic-plastic stress distribution at edge of hot spot weld is used for strength calculations. To obtain exact and reliable results for finite element analysis of spot welds, which are generally very small relative to other dimensions, sub-modeling technique is applied. The proposed numerical calculation scheme allows one to take into account the material parameters and geometrical non-linearity effects related to a gap between thin plates, buckling, etc. We provide the analysis of elastic and elastoplastic behavior of specimens with various configuration of spot welds subjected to tensile and compressive axial loads. [ABSTRACT FROM AUTHOR]