Equivalence Between the Combined Approximations Technique and Krylov Subspace Methods

The objective of this Note is to examine the equivalence between the CA technique and Krylov subspace methods. It is shown that the CA technique is a preconditioned Krylov subspace method. Based on this connection, it is briefly outlined why the CA technique will converge to the exact solution when the number of basis vectors is increased. The ramification of the present research on the practical issue of integrating static reanalysis techniques with structural optimization procedures is also discussed.