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By using the Eurocode 2 designing standard it is imposed, in some situations, to control cracking so that the requirements concerning the durability are satisfied.

For a correct verification of crack widths, the user has to set the real reinforcement area used at reinforcing the planar elements.

For example, the structural model from Figure 1 is considered. After a first run of the Concrete Expert (considering the theoretical reinforcement areas, which are automatically calculated), it is noticed that, for the selected element (Figure 1), the crack width verification is not satisfied. It is chosen to define the real reinforcement area for the selected element.

How is the global real reinforcement defined in a planar element for cracking control
Figure 1. Error encountered at cracking control


Note: On the command line, Advance Design will warn us every time when the maximum crack width is exceeded on the linear or on the planar elements.

In order to define the real reinforcement area for a selected planar element, the "Reinforcement definition" option is chosen from its properties window (Figure 3a). The real reinforcement which will be used (fabrics or individual horizontal bars) can be chosen from the "Global definition" section. In this case, a reinforcement with fabrics is used (Figure 3b).

How is the global real reinforcement defined in a planar element for cracking control
Figure 2. Definition of the global real reinforcement in a planar element


Note: In the dialog window Assumptions > Reinforced Concrete Design > Calculation Assumptions > Trusses, a list with the available fabrics can be viewed (Figure 3).

How is the global real reinforcement defined in a planar element for cracking control
Figure 3. Types of fabrics


After re-running the Concrete Expert, it will be noticed that the verification regarding the maximum crack width is satisfied. The obtained results are shown in Figure 4.

How is the global real reinforcement defined in a planar element for cracking control How is the global real reinforcement defined in a planar element for cracking control


         Figure 4. Crack width along the local x-axis in planar elements (wkx)                                  Figure 5. Crack width along the local y-axis in planar elements (wky)