Approximate techniques of strctural reanalysis

Abstract A study is made of two approximate techniques for structural reanalysis. These include Taylor series expansions for response variables in terms of design variables and the reduced basis method. In addition, modifications to these techniques are proposed to overcome some of their major drawbacks. The modifications include a rational approach for the selection of the reduced basis vectors and the use of Taylor series approximation in an iterative process. For the reduced basis a normalized set of vectors is chosen which consist of the original analyzed design and the first-order sensitivity analysis vectors. The use of the Taylor series approximation as a first (initial) estimate in an iterative process, can lead to significant improvements in accuracy, even with one iteration cycle. Therefore, the range of applicability of the reanalysis technique can be extended. Numerical examples are presented of space truss structures. These examples demonstrate the gain in accuracy obtained by using the proposed modification techniques, for a wide range of variations in the design variables.