At the stage when seismic loads are being resisted by the pier, it is most common to ignore the concrete cover outside the reinforcement core. Program provides an option to either allow or disregard this cover in design calculations. To ignore the cover, choose the option for Column core area. To consider the cover as intact use the full concrete area option. This choice can be made on the Seismic Design Parameters screen.

Program allows four rebar patterns to be placed in columns. These are circular, rectangular, intersecting hoops and general pattern. For circular and rectangular patterns, the core area is circular or rectangular passing through rebar positions as vertices. For intersecting hoops and the general pattern, the core area is the bounding rectangle of the rebar pattern.