Numerical simulations with group fastenings with Sheh Kai screw anchors with the non-linear FE-Program MASA (which is very suitable for such investigations) and with non-linear spring models. Varied will be the number of anchors in a group (n = 1 to 9), embedment depth, anchor spacing andconcrete compression strength. The simulation conditions will be chosen such that combined bond and concrete failure can be expected. From the results of the simulations a design method will be developed.