Abstract
The article presents an original method for verifying reinforced concrete elements under biaxial bending with axial force, in structures subjected to seismic action. This method was easily implemented in automated calculation programs based on numerical analysis. The nonlinear behavior of the reinforced concrete cross section was considered. More importantly, we propose a new method of presenting the results of numerical analysis. This representation involves a two-dimensional graph that can be printed on paper, and it shows the boundary between the resistance reserve of the analyzed element and the direction of horizontal loading. The described method exhibits a very good convergence, allowing results to be calculated and presented rapidly to the program user. The presented method can be successfully applied to any type of geometry and reinforcement.