Part  C  -  Minimum  Requirements  on  geotechnical  investigations

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4.2.2.2  Laboratory  tests
The  results  of  laboratory  tests  shall  be  fully  documented  and  described  for  each  typical  soil
property  (e.g.  grain  size  distribution  curves,  compression  test  results,  shear  test  results),  so
that  any  interested  reader  will  be  able  to  interpret  the  results.  The  test  set-up  has  to  be  described ­
  in  each  case.  If  standardised  tests  have  been  used,  reference  to  the  standard  will  be
sufficient.
The  results  of  compression  tests  shall  be  provided  in  the  form  of  pressure  settlement  curves
and  time  settlement  curves,  with  indication  of  load  stages  and  consolidation  times.  Documentation ­
  of  the  results  shall  also  include  data  on  equipment  dimensions  and  the  way  of  mounting
the  soil  samples  in  the  equipment.  The  results  of  soil  strength  tests  shall  be  shown  in  conformity ­
  with  applicable  standards.
The  results  of  the  laboratory  tests  shall  be  provided  in  the  form  of  tables,  sorted  by  borings,
sampling  depths,  and  sample  numbers.
4.2.3  Summary  of  investigation  results  (ground  description)
The  results  of  the  field  and  laboratory  tests  shall  be  compiled  in  a  geotechnical  site  description ­
  forming  part  of  the  geotechnical  site  survey  reports.
Grain  size  distribution  curves  shall  be  combined  to  grain  size  bands  of  the  main  soil  types
where  applicable.  The  ranges  and  mean  characteristic  values  of  the  soil  mechanical  parameters ­
  of  the  main  soil  types  shall  be  indicated  for  each  exploration  point.  These  data,  if  reasonable, ­
  should  be  compiled  to  establish  typical  foundation  soil  profiles  for  individual  areas.  If
necessary,  information  should  be  provided  regarding  use  of  the  characteristic  soil  mechanical
parameters  in  the  planned  foundation  design.
4.2.4  General  ground  assessment
The  general  ground  assessment  shall  include  an  evaluation  of  the  soil  and  subsoil  properties
at  the  project  site  with  respect  to  its  suitability  for  the  construction  of  foundations  for  offshore
structures,  both  with  regard  to  load  carrying  properties  and  to  the  feasibility  of  different  foundation ­
  concepts.

4.3  Soil  and  foundation  expertise
4.3.1  Content  of  soil  and  foundation  expertises
The  soil  and  foundation  expertise  must  contain  at  least  the  following  as  an  independent  part
of  the  geotechnical  report  according  to  DIN  4020  in  the  respective  project  phases:
•  a  general  description  of  the  site  in  geological  and  geotechnical  terms,
•  notes  regarding  the  spatial  orientation  of  discontinuities,  provided  they  are  relevant,
•  the  major  construction  data  as  foundation  criteria,
•  the  geotechnical  site  assessment  with  reference  to  construction  measures,
•  a  critical  assessment  of  the  findings  regarding  the  findings  listed  in  the  geotechnical  site
survey  report  in  coordination  with  the  structural  setup,
•  specification  of  design  profiles,
•  determination  of  the  soil  characteristics  and,  if  necessary,  of  the  computation  methods  or
computation  model,
•  if  applicable,  information  about  obstructions  to  driving  and  suitable  methods  for  piling  and
mudmat  installation,
•  description  of  possible  foundation  designs  including  their  geotechnical  evaluation,