Page 161 - Pipelines and Risers

134 Chapter 9

Table 9.5 Fatigue Assessment Results.

1956 2.06
2436 2.71
I 2571 I 0.19 I 0 I
I 2704 I N/A I N/A I

3319
3444 0.17 0.003
Note. Span damage given as NIA indicates that the span is not among the first ten eigen
modes.

Supports are placed at the mid-spans of all the unacceptable locations. Optimisation of the
support location is possible to reduce the rock volume by placing the supports nearer the span
shoulders.
Further static and modal analyses and a fatigue re-assessment were carried out. The results are
given below.

--M 14Fl-0412
-Ms.Fr-0.408
--M 8.~m.371
- M7.hd952
- 8.Fr -0.34
M
--MS,Frm313
--M 4.~rmz98
3-- - --M3.Fr-029
2 --
1, --M 1,Fr -0.225

l""""':"""'":'"'"'"''""''l
1500 2wo 2500 MW 35w
Chainage (rn)
Figure 9.7 In-Line Mode Shapes, 40" Pipe with Supports.