GGU-RETAIN: "Subgrade reaction moduli" menu item

If the analysis is to be performed for an elastically bedded wall toe, it is necessary to enter a modulus of subgrade reaction. In this dialog box you can enter the profile of the subgrade reaction moduli.

The number of subgrade reaction moduli can be adapted to your system using the "x subgr. modulus(i) to edit" button. It must be noted, however, that in this case the depth data is with reference to the excavation base and are positive downwards, regardless of the initial setting of the "Use absolute heights" check box. You can also have the program take care of the depth input by activating the "Lock to layer boundaries" check box. Now, you only need to enter the values for the modulus of subgrade reaction.

The following modulus of subgrade reaction profile was modelled using the values shown in the dialog box:

The tangential bedding is given in the "µ(ks)" field as a multiple of the horizontal bedding. However, the factor is generally of little importance, since the wall toe is considered to be vertically non-displaceable, meaning that deformations in a longitudinal direction, and any associated tangential subgrade reaction moduli, are small.