Sequentially linear analysis avoids convergence problems typical of non-linear finite element analysis by directly specifying a damage increment instead of a load or displacement increment. A series of linear analyses is used to model highly non-linear behavior without an iterative solution algorithm. The primary contribution herein is the extension of sequentially linear analysis to non-proportional loading, through an algorithm which selects the critical integration point to which a damage increment is applied. An orthotropic cracking model is presented which parallels the traditional fixed smeared crack concept. The non-proportional modeling framework is demonstrated through simulation of experimental results and settlement damage to a masonry façade.
