sin αst

LIST OF ATTACHMENTSSTRUCTURAL VERIFICATION OF SHAFT
Figure G.1: Indication of studied cross-section and geometric data
For both fatigue and ultimate limit states, the following requirement must be met:
Where
�design is the design stress from the load case
fk is the characteristic material strength
�m is the partial safety factor for the material
�f is the partial safety factor for the load
The shaft is manufactured from steel S235, which has a characteristic ultimate strength of
360 MPa and a characteristic amplitude fatigue strength of 180 MPa [54 , TB 1-1]. The
stated fatigue strength is converted into an allowable stress range by multiplying the am-
plitude value by 2, thus making the fatigue strength 360 MPa. This is a conservative value,
as it is valid for a fatigue stress ratio of -1.
The values of the partial safety factors are established in accordance with IEC 61400-2
under the assumption of so called full characterisation of the material properties [5, p. 89].
This implies that factors such as environmental effects and manufacturing methods have
been taken into consideration when determining the material properties.
Condition �m �f
Fatigue strength 1.25 1.0
Ultimate strength 1.1 3.0
Table G.2: Partial safety factors in accordance with IEC 61400-2
From this the ultimate limit state is calculated:
190
�lim.u �
�design �
f k
� m � f
f k
� m � f
� 109 MPa
(G.1)
(G.2)