The elastic-plastic design utilizes the plastic reserves of the cross-section. In the analysis, EL-PL takes into account the interactions of the combined design loads. The program examines if the limiting internal forces remain under the specifications in the perfect plastic state. This analysis includes the check of the ratios (b/t), i.e. width/thickness, according to DIN 18800 part 1, table 15, considering the factors Alpha of the compression zones.
Besides the interaction conditions of DIN 18 800 Part 1, design according to Kahlmeyer is possible for singly and doubly symmetric box- or I-sections in case of a uniaxial bending stress around the strong axis.
In the case of single or double symmetric I-sections and box-shaped cross-sections or pipes, the limiting internal forces in the plastic state can be calculated according to the procedure from Rubin. With these very comprehensive methods of analysis, the most favorable results can be obtained in the majority of cases.
EL-PL is able to design a great variety of rolled and welded I-sections, combined sections, and singly symmetric box- and I-sections according to different methods.