58 
Part B - Verifications and approval requirements 
Core content 
Descriptions according to 
BSH Standards (2014 and later) 
DIN 
EC-7 
Geotechnical 
investigation report 
GTE* 
Preliminary ground investigation 
report Main ground investigation 
report 
Geotechnical 
report (DIN 4020) 
Geotechnical 
design report 
(DIN EN 1997-1 and 
DIN 1054, 2011 and 
later) 
Characteristic 
parameters, subsoil 
model and 
foundation proposal 
GTE* 
Subsoil and foundations survey 
(development phase) Subsoil and 
foundations survey (design phase) 
Stability and service 
ability verifications 
PEG 
(arch.)** 
Geotechnical design report, (where 
necessary, including a supplemen 
tary expert opinion on the “cyclics”) 
Geotechnical 
design report (DIN 
1054 until 2010) 
* GTE: Geotechnics expert 
** PEG (arch.): Planning expert for geotechnics on behalf of the architect 
Table 3-1: Content, descriptions of and responsibilities for the documents in accordance with 
the Standards Ground Investigations and Design and comparison with the corresponding de 
scriptions in the respective normative standards. 
The exact definition and separation of the areas of responsibility to be covered by the geo 
technics expert and the planning expert for geotechnics are the responsibility of the appli 
cant. 
Note: 
According to DIN EN 1997-1, 2.8, A Note to (3), both the geotechnical report and the geotech 
nical design report may be compiled by the same person/organisation, if this person/organisa 
tion has acquired the necessary expertise and experience. 
From a geotechnical viewpoint, offshore structures are extremely complex structures, the 
foundations of which are classified as belonging to geotechnical class 3 (GK 3) in accordance 
with DIN 1054 (earthwork and foundation engineering and geotechnical measures with a high 
geotechnical risk). They require their foundation design to be conducted by a planning expert 
for geotechnics (a geotechnical expert with thorough knowledge of and experience in this 
area). Where necessary, the applicant, resp. approval holder, shall define the tasks to be car 
ried out by the planning expert for geotechnics and those to be carried out by the geotechnics 
expert in accordance with the Standard Ground Investigations, Part A, Section 4. 
Beyond the uncertainties of the local subsoil situation, it is also necessary to consider the lim 
ited possibilities of deterministic calculation models in geotechnology when designing the 
foundation elements of offshore structures. 
The achievable “accuracy” of numerical model calculations including the subsoil is signifi 
cantly lower than that of design components due to the implementation of what are, by ne 
cessity, highly simplified stress deformation relationships and contact surface conditions. As 
a rule, therefore, variations of the significant geotechnical influencing parameters shall be un 
dertaken by means of which their influence on the draft target is limited and which indicate 
how the overall structure will “behave” within these limits to a sufficient degree of probability 
(Appendix 3-V). 
This procedure is essential for all verifications in which subsoil deformations are contained as 
a target or influencing parameter, in which changes in the subsoil properties have to be con 
sidered, and in which assumptions are made regarding model parameters due to the lack of 
determinability.