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Part C - Minimum Requirements on geotechnical investigations 
3 Requirements on laboratory testing 
3.1 Standard laboratory tests 
The standard laboratory tests for cohesive and non-cohesive soils are set out in Tables 7 
and 8 which are suitable for describing the state of the soil as well as for determining the fun 
damental characteristics of the ground conditions. The geotechnical expert determines the 
tests to be carried out on a case-by-case basis, the type of testing methods, the sample qual 
ity required as well as the soil mechanical parameters. Further laboratory tests may be expe 
dient for measuring the foundation structure depending on the planned foundation type. 
Table 7: Suitable laboratory tests for assessing non-cohesive soils. 
Test type 
Standard 
Quality of the sample 
(DIN EN ISO 22475-1) 
Soil mechanical 
parameter 
Classification and status description 
Particle size distribution 
DIN 18123 
Min. 4 
degree of non-uniform 
ity, coefficient of grada 
tion 
Bulk density 
DIN 18126 
Min. 4 
Loosest and densest 
state 
Density 
DIN 18125-1 
Min. 2 
density, buoyant den 
sity 
Lime content 
DIN 18129 
Min. 4 (5) 
Lime content 
Deformation behaviour 
Compression test 
(Oedometer test) 
DIN 18135 
4 but mounted sample 
with initial in-situ den 
sity 
Stiffness modulus, co 
efficient of consolida 
tion, coefficient of sec 
ondary compression, 
derived: coefficient of 
water permeability 
Triaxial test 
DIN 18137-2 
1, but also treated sam 
ples 
Shear stress-strain 
curves, volume change 
and axial deformation 
Shear strength 
Direct shear test 
DIN 18137-3 
1, but also treated sam 
ples 
Friction angle <p’ 
(o’ = 0) 
Triaxial test 
DIN 18137-2 
1, but also treated sam 
ples 
Friction angle <p’ 
(o’ = 0) 
It can be expedient to carry out investigations of a limited scope on board the survey vessel 
or the jack-up rig to obtain findings for planning further field investigations which can subse 
quently be carried out relatively promptly.