Incompressible subsoil

At a certain depth below the ground surface it is possible to specify incompressible subsoil. If the pile exceeds this specified depth then all beam elements found below this value are fixed instead of being spring supported. The pile then essentially experiences no settlement. If there is incompressible subsoil below the pile heel but not deeper than the reach of influence zone below the heel, the depth of influence zone for the stiffness computation is then reduced such that the influence zone just reaches the incompressible subsoil. This way also the incompressible subsoil below the heel increases its stiffness and consequently also the bearing capacity of the pile heel. If the incompressible subsoil is found below the reach of the influence zone, then it does not influence the analyzed pile.