Loadbearing structures and detailed design - Concrete Structures for Wind Turbines - page 124

Table 4.2 Designations for design load cases

DLC Design load case DIN EN 61400-1 section

NWP Normal wind profile model 6.3.1.2

NTM Normal turbulence model 6.3.1.3

EWM Extreme wind speed model 6.3.2.1

EOG Extreme operating gust 6.3.2.2

EDC Extreme wind direction change 6.3.2.3

ECG Extreme coherent gust 6.3.2.4

ECD Extreme coherent gust with change

of wind direction

6.3.2.5

EWS Extreme wind shear 6.3.2.6

Alternatively, the wind turbulence models can be handled as follows [9]:
1. Submission of three representative analyses with different realisations of the
turbulent wind field (various wind seeds). It must be shown that the moving 3 s
average of the wind speed time series satisfies the value required for the 50-year
gust/1-year gust once in each of the three simulations at any point in the area swept
by the rotor. At the same time, it has to be verified that the statistical parameters of
the turbulent wind field satisfy the requirements according to DIN EN 61400-1 [16]
for all three time series.
2. Submission of three representative analyses with different realisations of the
turbulent wind field (various wind seeds). It must be shown that the moving 3 s
average of the wind speed time series satisfies the required value for the 50-year
gust/1-year gust in each of the three simulations for at least three points at non-
adjacent positions within the area swept by the rotor. It is then unnecessary to
verify the statistical properties of the wind speed field according to DIN EN
61400-1 [16].
Note: The three representative simulations should be selected from a larger number of
simulations, for example 10, for both alternatives.

4.5.4 Partial safety factors according to DIBt guideline
The partial safety factors given in Table 4.3 should be used for the design load cases
according to Section 4.5.3 (see Table 4.1 in conjunction with Table 4.2).
Partial safety factors

g M for the ultimate resistances of concrete structural components
can be found in DIN 1045-1 [33] 5.3.3 (Table 2).