The design according to EN 1992‑1‑1 requires the definition of "concrete durability", so the program can automatically apply the concrete cover, for example. This type for concrete design is therefore only available if you have specified the standard EN 1992 for the design. This type does not exist for any other design standards. It is then necessary to manually define the concrete cover for each structural component.
Exposure Classes
The Exposure Classes tab provides the exposure classes for the reinforcement and the concrete. You can control the selection using the check boxes and lists.
By selecting the "No risk of corrosion or attack" option for the "Exposure Classes for Reinforcement", you define the X0 exposure class.
The X0 exposure class plays a role for foundations without reinforcement and frost, as well as for internal components without reinforcement. In the current state of development, however, it is not possible to design unreinforced foundations. Therefore, this option plays a minor role. If you use the X0 exposure class anyway, the program assumes a minimum concrete cover of 20 mm for the design.
In the "Exposure Classes" tab, you can also make multiple selections. According to the info graphic on the right of the dialog box, the exposure class is then determined, which is governing for the concrete cover on the basis of this selection.
The relevant exposure class is shown in black in the infographic. The exposure classes that play a minor role in this combination are shown in blue. This allows you to quickly check the possible combinations of exposure classes for different structural components.
Name
The program generates a name from the selected exposure classes, which describes the concrete durability type. You can use the
button next to this generated name to edit the entry and assign a user-defined name. This contributes to clarity, especially in the case of models with many different types, and makes it easier for you to assign the types to the individual components.
Assigned to
This section specifies the numbers of members and surfaces, which the selected concrete durability type has been assigned to. Use the
button to add or deactivate further objects.
Concrete Cover Options
The Concrete Cover Options tab provides you with the option to specifically adjust the concrete cover resulting from the exposure classes.
Structural Class
The options of this section allow you to increase or decrease the structural class, as described in EN 1992‑1‑1, Table 4.3N, provided that there are special conditions in the service life or the concrete properties. As an alternative, select the "User-defined structural class" from the list.
Reduction of Concrete Cover for Durability
The check boxes in this section allow you to reduce the concrete cover in the case of stainless steel reinforcement or special protective measures.
Allowance for Deviation
The allowance Δcdev is the allowable negative deviation in construction that should take into account unintended deviations. In this section, you can use the "Concrete cast against uneven surfaces" option to increase the nominal size. As an alternative, you can enter a user-defined allowance for deviation.