Part B - Verifications and approval requirements 
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• Potential change in the arrangement of foundation elements due to influences such as cyc 
lical creep of the subsoil, accumulated deformation (hysteresis) and 
• Potential change in the mechanical properties of the subsoil due to influences such as pore 
water pressure accumulation (liquefaction), consolidation, deconsolidation. 
It shall be demonstrated that 
• either these mechanisms do not occur 
• or that these mechanisms have been adequately taken into account in the design 
• or that these mechanisms will be adequately observed during installation and operation and 
that suitable measures will be taken to compensate for them if necessary. 
3.3.2.5.2 Verifications for foundation elements 
As a minimum requirement, the following shall be investigated, documented and given due 
consideration in all respective verifications: 
• The process engineering of the installation and effects of the installation process 
• The description and modelling of the significant interactions between the subsoil and the 
structure as the basis and input parameters 
- for the verifications pertaining to the external load capacity of the foundation and its ele 
ments 
- for the verifications pertaining to the internal load capacity of the foundation elements 
and 
- for the natural frequency analysis of the offshore structure 
• The influence of stability properties of the seabed on the stability against collapse and on 
the serviceability of the foundation, the entire structure and its components in accordance 
with B3.3.2.5.1 
• The effects of cyclic and dynamic loads (degradation and liquefaction) 
• The constraint stress on structural elements and add-on components due to permanent 
subsoil deformation 
• The safety against shifting of ballast material. 
For all verifications pertaining to foundation elements, the lower and upper limits for the rele 
vant subsoil parameters shall be varied in an unfavourable combination. Where the ductility of 
the subsoil and the structure is adequate, verifications based on characteristic parameters are 
sufficient; the respective ductility shall be demonstrated. As a minimum requirement, the 
lower and upper limits for the stability of the foundation elements shall be determined and 
varied in an unfavourable combination for the purpose of analysing the natural frequency of 
the overall systems. 
Special verifications which are required for pile foundations: 
• The axial pile load capacity and safety 
• The lateral pile load capacity and safety 
• Axial deformation and shifting estimates (settling, inclination and rotation) 
• Lateral deformation and shifting estimates and 
• Pile group effects and interactions between individual foundation elements (e.g. in tripile, 
tripod and jacket structures).