Some aspects on efficient solution of creep problems

Integration of inelastic constitutive models by implicit schemes, require local Newton’s iteration to solve the discretized non-linear evolution equations at the integration point level. Choise of the starting values in the Newton’s iteration affects on the success of the iteration at the local integration point level. This note describes a simple modification on the approach proposed by Schreyer giving increased robustness on the local iteration process. Also the effect of line search and quasi-Newton methods in the solution of the global equilibrium iterations is investigated.