Untitled - Teknik Kelautan / ITB

Retrofit of Corroded Offshore Platform by Grouting
M.Suarjana 1 , M.Kurnia 2 & D.Pratomo 3
1 Associate Professor Civil Engineering Department, Institut Teknologi Bandung
(ITB), Ganesha No 10 Bandung 40132, Indonesia
2 Master Program Student of Civil Engineering Department, Institut Teknologi
Bandung (ITB), Ganesha No 10 Bandung 40132, Indonesia
3 Former Student of Civil Engineering Department, Institut Teknologi Bandung
(ITB), Ganesha No 10 Bandung 40132, Indonesia
Email: msuarjana@si.itb.ac.id, mahdiankurnia@gmail.com,
derip123civil@gmail.com
Abstract. Structures of the jacket type offshore platforms are usually made of
tubular steel. Steel structures for offshore platforms are very prone to corrosion
problems. Corrosion will reduce the strength and stiffness of the member and joint to
the extent that the corroded members and joints may be not strong enough to
withstand the load imposed on the platform. An effective method to retrofit the
corroded members and joints is to conduct grouting of the member and joint. The
grouting method is cost effective and do not require shutting down platform
operations during the process. In this study, a finite element analysis complemented
with manual calculations was performed to review the effectiveness of grouting
systems for retrofitting a corroded offshore platform. The full finite element model
of the platform was developed to analyze the internal forces of the members and
joints. Stiffness of the grouted members was modified to include the composite
action of steel tubular members and the grout. The internal forces were used to check
by manual calculation the strength of members and joints based on API RP 2A WSD
and NORSOK codes and other published empirical equations.
Keywords: corrosion, grouted joint, grouted member, offshore platform, retrofit
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