Answer:
1) The default orthogonal combination factor is set to 0.3 (30%). This value can be changed by going to Edit Parameters of Edition in the Load Cases & Combinations (Image 1)
2) Under the Load Cases tab, create the seismic load cases in the X and Y directions with Qe as the Action Category. Activate the 'Additional Settings| Consider X and Y independently' option. Then, specify the direction under the Additional Settings tab (Image 2)
3) Under the Design Situations tab, select the Edit Combination Wizard button. In the Standard Options tab, make sure that the Include orthogonal combinations option is activated (Image 3)
4) The generated COs including the orthogonal combination factor are listed in the Load Combinations tab (Image 4)
