GGU-STABILITY: "Maximum nail forces + punching" menu item

Calculation of the maximum nail forces using tension members is in analogy to the description given in the "Maximum nail forces" menu item.

The value proposed for the earth pressure e,d in the "Calculate maximum nail forces" dialog box is also adopted for the punching verification. After confirming or editing of the calculated earth pressure value, the following dialog box will appear:

The maximum nail forces, determined in accordance with the descriptions of Section “"Maximum nail forces" menu item”, are shown in the list in the dialog box. The maximum nail value is multiplied with the horizontal separation and suggested as design value for punching verification (see entry after "Verification with [kN]:"). This value can, if wished, be edited. If you are carrying out several calculations with slip bodies but want to calculate the punching safety factor with a different value to that suggested, you can use the "Retrieve old verification value" button to bring back the last entered value into the input box.

After this, punching verification is done. The pressure under the punching area will be subtracted from the nail force, in accordance with EC 2. The pressure is taken as the reduced earth pressure (see above). Besides this information the following must be given, in accordance with EC 2, for punching verification:

• Effective height of concrete shell in the verification area, as % of concrete shell thickness;

• Width of nail slab (= height):

• Present bending reinforcement;

• Concrete used;

• Steel used.

These inputs can be made in the lower part of the dialog box. Verification will be carried out after pressing the "OK" button and the results are displayed.

The dialog box contains all decisive values for verification. Using the "Again" button, you can repeat the verification with new input values.

If, in the menu item "Nail wall/Verifications", you have activated the "Punching verification" check box, the most important design values will be presented in the "Nail wall legend" on the screen.