Minimum cost design of RC frames using the DCOC method Part II: Columns under biaxial bending actions

The DCOC-based numerical algorithms developed in Part I are generalized to the minimum cost design of RC frames in which columns are subjected to biaxial bending. All columns in each floor are assumed to have the same cross-section. Likewise, all beams are assumed to have the same section over their entire length. To account for the variation of forces along the height of the columns or the length of the beams, the steel ratio is allowed to vary freely. Real problems are solved to demonstrate the efficiency and practicability of the algorithm developed.