Dummy plate properties in PLAXIS 3D.

Question

Dear all, When modelling a pile with a section of 100cm by 320cm using a volume element in plaxis 3D, one is required to introduce a dummy plate such that the plate will not affect the results. 
 My question is if my real E is 32 GPa and I know that the unit weight must be set to zero, what will be the value of E1 (assuming that E1=E2) and d (thickness)? 
 In the output, what value do we multiply with the forces to get an actual value of N,M and V. 
 
 Thanks.

Stefanos Papavasileiou · Answer

Dear Abdirahman, 
 In principle, you can pick any factor to reduce the parameters, which you need to keep in mind when checking the results in Output. 
 We suggest picking a factor of 1E4 or smaller. 
 Apart from the zero unit weight, please keep in mind to not include any interface between the dummy plate elements and the volumetric cluster: we need to make sure that the nodes are fully connected (so no slipping of the plate inside the wall).

Stefanos Papavasileiou · Answer

Dear Nadeem, 
 The thickness of the plate should remain the same.