000173819 001__ 173819
000173819 005__ 20190117220043.0
000173819 037__ $$aCONF
000173819 245__ $$aVibration-Based Parameter Identification of Large Scale Offshore Structures
000173819 269__ $$a2011
000173819 260__ $$c2011
000173819 336__ $$aConference Papers
000173819 520__ $$aStructural health monitoring has increasingly become a hot research topic for engineering structures. While much improvement has been made in advances of sensing, communication and computer technologies, identification of structural parameters based on vibration signals is a promising but difficult task due to the ill-conditioned nature of inverse analysis. For offshore structures, the challenge is even greater as they are usually very large and subjected to severe environmental loads including dynamic wave load. This keynote focuses on offshore jack-up, a type of mobile self-elevating drilling unit used in the oil and gas industry. A jack-up rig typically comprises a buoyant hull supported by three lattice legs, each resting on a large inverted conical footing called spudcan. As jack-up peration moves into deeper waters and harsher environments, there has been an increasing demand to model the jack-up structure more accurately by accounting for spudcan fixity (i.e. soil stiffness at spudcan footing). Due to the large size of jack-up rig, a substructure approach is essential so as to reduce the effort of forward analysis and inverse analysis. In view of the difficulty in measuring wave forces, a predictor-corrector procedure is incorporated to compute the input force instead as identification progresses based on an improved genetic algorithm method recently developed by the authors. The performance of the proposed strategy in identification of sudcan fixity is demonstrated by numerical study, using a jack-up operating in the North Sea as an example.
000173819 6531_ $$aStructural identification
000173819 6531_ $$aGenetic algorithm
000173819 6531_ $$aOffshore jack-up
000173819 6531_ $$aSpudcan
000173819 6531_ $$aFoundation stiffness
000173819 700__ $$aKoh, C. G.
000173819 700__ $$aZhang, J.
000173819 700__ $$0242301$$aTrinh, T. N.$$g198411
000173819 7112_ $$aThe 14th Asia Pacific Vibration Conference$$cHong Kong, China$$dDecember 5-8, 2011
000173819 773__ $$tThe 14th Asia Pacific Vibration Conference
000173819 909C0 $$0252031$$pIMAC$$xU10237
000173819 909CO $$ooai:infoscience.tind.io:173819$$pconf$$pENAC
000173819 917Z8 $$x198411
000173819 917Z8 $$x198411
000173819 937__ $$aEPFL-CONF-173819
000173819 973__ $$aEPFL$$rREVIEWED$$sPUBLISHED
000173819 980__ $$aCONF