cranfield university mahadi abd murad an integrated structural ...

Figure 3.24: Finding the hoop stress concentration value ( K ) in the repaired steel
pipeline (i.e. at elements 5094 and 2141)
Figure 3.24 shows a simple method to measure the maximum values of not only
the hoop stress and but also strain at the notch root and away from the defect (nominal
area) before further study on stress concentration factor with composite repair can be
carried out in this section and strain concentration factor studies in the later section.
Basically, when the pressurised Model 3, as discussed in the earlier sections, was
repaired by the epoxy compound and composite wraps, apparently the points where the
maximum readings of stress and strain at the notch root or nominal area were measured
have been hidden beneath the repair. Therefore, the cut section tool, available in
ABAQUS 6.7.1, which is the only way to gain access to those two points was used. The
model was cut through the A-A section (x plane), as shown in Figure 3.24, in order to
measure the relevant readings. In fact by following this method, other studies can be
carried out such as measuring the size of element etc.
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