The 'DS1- Section 2.3 LRFD' design situation was created when combining the load cases for the static analysis. These design situations are also listed in the 'Concrete Design' folder of the navigator, as they may be relevant to the concrete design.
Double-click the DS1 design situation item in the navigator. On the 'Design Situations' tab of the 'Load Cases & Combinations' dialog box, the 'Concrete Design' option is activated and the second-order (P-Δ) theory is set.
