Analysis on external pressure bearing capacity of cylindrical shell based on measured geometric defects

  Objectives  The purpose of this paper is to study the way to establish finite element models with real geometric defects, and to predict and analyze the bearing capacity of a scale down pressureresisting cylindrical shell structure based on different types of defects.

  Methods  Therefore, a geometric defect extraction method based on quadratic transformation is proposed, then the method of introducing the measured initial geometric defect, which is expressed by double Fourier series, is established. Finally, the buckling capacity of scale down pressure-resisting cylindrical shell under external pressure is analyzed and obtained based on eigenvalue modal defect and measured defect.

  Results  The results indicate that Fourier series method only involves traversing of grid nodes and calculation of a few function values and can significantly improve the calculation efficiency of defect introduction without reducing the accuracy of calculation.

  Conclusions  Fourier series method can provide guidance for accurate analysis of ultimate bearing capacity of cylindrical shell structure and structural optimization design.