Issue 63

M. Khaise et alii, Frattura ed Integrità Strutturale, 63 (2023) 153-168; DOI: 10.3221/IGF-ESIS.63.14

thickness is maintained as per standard ISO/TS24817 [5, 12, 17, 36]. The thicker composite thickness behaves like a rigid body and because of this deformation start to occurs at the steel pipe in non-defected section. It is very important to optimize the repair composite thickness in order to avoid the plastic deformation of steel pipe in non-defected section. This indicates the composite repair thickness calculated based on the design standard is too conservative, which is good for safe repair design but it increases the repair cost as it needs a more composite material.

(a)

b) Figure 13: Plastic deformation away from defect region: a) numerical model; b) hydrostatic test [11]

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