Nonlinear and dynamic structural analysis using combined approximations

It is shown how the combined approximations (CA) approach, developed originally for linear reanalysis, can improve the solution efficiency of nonlinear and dynamic analysis problems. In such problems the analysis equations are modified repeatedly during the solution process. The CA approach is based on the integration of several concepts and methods. The advantage is that efficient local approximations and accurate global approximations are combined to achieve an effective solution procedure. Some numerical examples demonstrate how the CA method can be used as a general tool in various structural analysis problems.