An iterative combined approximation approach for structural static reanalysis of topological modifications
结构静态拓扑重分析的迭代组合近似方法

This paper presents an iterative combined approximation (ICA) approach for structural static reanalysis of all types of topological modifications. The proposed procedure is basically an approximate two step method. First, the newly added degrees of freedom (DOFs) are assumed to be linked to the original DOFs of the modified structure by means of the Guyan reduction so as to obtain the condensed equation. Second, the displacements of the original DOFs of the modified structure are solved using the ICA approach. And the displacements of the newly added DOFs resulting from topological modification can be recovered. In order to illustrate the application of the present method, the layout optimal design of stiffeners in the plate-shell structure is given. In the layout optimization, the strain energy sensitivity of the element and the rejection ratio are introduced. In each iteration, a number of elements may be deleted. To save computational effort, the ICA is used to perform the reanalysis to update the modified displacements of the structure. The results show that the ICA method is effective for structural static reanalysis of the topological modifications oven though the large topological modifications are made, and it is easy to implement on a computer.