Concrete Parameters

Once the Calculation Options dialog is opened and the Concrete tab is selected, the dialog shown below will appear on the screen.

Note: The content of the dialog shown above depends on a selected RC code; therefore, for other codes the appearance of the dialog may differ from that shown above.

The above dialog is used to set concrete parameters to be used during calculations of an RC structure element.

The upper part of the dialog shows a material database used. Pressing the (...) button opens the Job Preferences dialog on the Materials tab. A new material database may be selected there.

The above dialog also allows determining concrete parameters connected with a selected material database.

fc28 - field for selection of the concrete grade from the list of predefined grades or definition (using the keyboard) of the arbitrary concrete load capacity
Unit weight - field for defining the concrete unit weight which will be used for setting the column dead load
Aggregate Size - field for setting the aggregate diameter which determines the minimum longitudinal bar spacing for the column section level.

Additionally, for the ACI 318-14 code, if the Lightweight concrete option is selected then the Modification factor λ may be determined. This is the factor to reflect the reduced mechanical properties of lightweight concrete relative to normal weight concrete of the same compressive strength.

For Eurocode 2, you can also select a stress-strain relation used in calculations.