Abstract
Robust Incomplete Cholesky decomposition developed by Ajiz is based on the idea of stabilization for diagonal entries, and no breakdown can occur during the incomplete decomposition. In this paper, we consider convergence of new preconditioning which combine relaxation with dropping procedure for diagonal entries for the purpose of speed-up of the preconditioned CG iteration. Through numerical experiments for some realistic structural problems, the new approach with quasi robustness insures convergence rates of PCG method.