PSI - Issue 84

Ahmed Amir Khalil et al. / Procedia Structural Integrity 84 (2026) 1031–1038

1036

strength—in the columns along axes K and J (specifically K-12c, K-15d, and J-15d), which support the heavy loads of the primary hung equipment. Such high vertical stress is achieved as consequence of the high load supported and the weakening work necessary to install the shaped charges. The weakening process involves scarfing the additional steel plates to reduce the blast thickness to 9.85 cm, since the combined thickness of the flange and added plates is about 15.5 cm, making it difficult to remove with shaped charges. To achieve this reduction, scarfing is applied to the flanges and plates. However, due to the high stresses observed, additional strengthening measures are necessary. A special detail is implemented at these columns: four steel plates, matching the flange thickness and measuring 5.7 cm in width, are welded to the four flange edges over a height of 150 cm. Figure 6 illustrates the vertical stress contours in the boiler columns during the cutting and weakening stages, along with a photograph of the strengthening work performed.

a

Reinforcement plate

0 MPa

b

c

Scarfing

150cm

Section with scarfing and higher vertical stresses 190MPa

Fig.6 (a) Detail of vertical stresses in the columns K-15d at ground level in the cutting stage, (b) overview of the stresses at the ground level, (c) detail of the work performed in the strengthened column

a

b

Fig.7 Perspective view, side by side comparison, (a) real case, (b) AEM simulation.