Used along with the material yield to determine the cutoff yield value to be
used.
Yield (cutoff) = Material yield / Cutoff
value
Notch Class - Transverse Location_X
Notch class definition considered for the fatigue limit calculation for the
normal stress component in the transverse direction (perpendicular to the
axis of the weld) at ‘X’.
Note: Where ‘X’ can be any evaluation
location.
Notch Class - Longitudinal Location_X:
Notch class definition considered for the fatigue limit calculation for the
normal stress component in the longitudinal direction (parallel to the axis
of the weld) at ‘X’.
Notch Class - Shear Location_X
Notch class definition considered for the shear stress component at ‘X’.
Material Grade - Location_X
Grade of shell material used. Options – S355, S235. Also, interpolation for
in between values is supported. Location specific.
Material Yield - Location_X
Material yield. Location specific.
Groove Gap (b)
Gap between the two plates at the location of weld. b in Figure 1.
Groove Depth (h)
Height of the groove from the top, calculated as t - c from Figure 1.
Groove Angle (alpha - deg)
Angle of the groove/plate walls at the location of weld. a in Figure 1.
Note: Refer to Figure 1 for the groove parameters. These groove
parameters have been derived from the En 15085 standard. Refer to
Common Classification Parameters.
Figure 1.
Static Assessment
The following process is followed for Static assessment:
Retrieve the six components of stress from the element at the evaluation
location.
Calculate the von Mises stress value using these stress components.
Retrieve the material yield value from the Points context.
Determine the static strength ratio: element von Mises stress / material
yield value
Frequently Asked Questions
What is the Cutoff Parameter?
It is a safety factor to be used along the yield strength. This value is
used to determine the upper limit for the fatigue
strength.
Fatigue strength (cutoff) = Material yield /
Cutoff value
How does the exponent x interpolation work?
In case of DVS 1612, the value of exponent ‘x’ depends on the material
grade and has different values based on the grades of S235 and S355.
But, whenever the base/web material does not fall into either of these
grades, then the tool uses an interpolation technique to find the
intermediate ‘x’ exponent value. Figure 2.
The process of interpolation is as follows:
The tool retrieves the material grade/yield assigned for the
particular location from the classification area.
The tool also identifies the fatigue class/notch case for the
particular location from the classification area.
Based on this fatigue class, the tool retrieves both the values
of exponent 'x' from the “regulation_ data” folder belonging to
the grades S235 and S355.
An initial check is carried out to determine if the material
yield is higher than the highest grade (S355) or if it is lower
than the lowest grade. If so, then the tool considers the
exponent 'x' to belong to the highest/lowest grade respectively
for calculation.
If the material yield value is in between the two grades, then
the tool calculates the intermediate value of exponent ‘x’ using
a linear interpolation technique. The calculated value of
exponent ‘x’ is then used for utilization calculation.
