Algorithm for Non-proportional Loading in Sequentially Linear Analysis

Sequentially linear analysis (SLA) is an alternative to the Newton-Raphson method for analyzing the nonlinear behavior of reinforced concrete and masonry structures. In this paper SLA is extended to load cases that are applied one after the other, for example first dead load and then wind load. It is shown that every nonlinear analysis step can be made in just two linear elastic analysis steps. The proposed algorithm is extremely robust, which is demonstrated in a prestressed concrete beam analysis. A comparison is made between results of SLA and Newton-Raphson with arch length control.