As additional information: According to TBDY 2018 Article 4.5.8, effective section rigidities are used to determine the section properties of reinforced concrete elements. Moving and fixed vertical calculation values with effective section stiffnesses are given as G' and Q' in the program. It uses effective section stiffnesses for earthquake-effect load combinations. In other words, if seismic combinations are active in element design effects, combinations with G' and Q' values appear. From TBDY 2018: In reinforced concrete designs, the 1.4G+1.6Q combination is used independently of earthquake combinations. Definitions of loading and combinations are given in the building general information report.