A GENERAL AND EXACT ANALYSIS METHOD FOR STRUCTURES WITH LOCAL STIFFNESS CHANGE

This paper is concerned with the reanalysis of structures with local stiffness changes. The problem arises in finite element analysis of structures with some damaged components or yielding elements. A new algorithm is presented in which the reanalysis of the complete new structure is rendered unnecessary. An exact result is obtained with some algebraic manipulation of the LDLT factors of the original stiffness matrix. The computational time is same as that consumed in other methods. In addition, the present method is general. It is applicable to any type of structure, such as bar抯 structure system or continuum problem. Numerical examples are provided, showing that the new algorithm is effective in calculating structures with local stiffness changes.