Numerical study of the effect of Base Isolated (neoprene) on the dynamic response of the installed module on the FPSO deck

Abstract

Significant advantages of FPSO in the ability to transfer and extract from offshore wells have led to their widespread applications. Kind of different modules is installed on the top of these platforms, where one of the major engineering concerns is choosing the location of these modules on the FPSO platform deck in order to reduce the effects of environmental forces. Typically, these modules are analyzed and designed based on the maximum linear acceleration extracted from the shipchr('39')s spectral analysis, using a quasi-static method. The main purpose of this research is the analytical study of these modules response under dynamic excitation due to the wave effect. This research has been done in two parts. First, the dynamic response of different parts of the shipchr('39')s deck has been analyzed under the effect of wave force and proper location for these modules is recommended. For this purpose, first with modeling and analysis performed in MAXSURF software, the shipchr('39')s dynamic responses at different points of the deck have been calculated. Then these modules have been analyzed against the deck response considering base isolation at the module bases in the second part. The obtained response has been applied to two modules as a case study in Sap2000 software. The result shows that base shear and displacement have a verity response in the function of base isolation stiffness. Due to the extension of the shipchr('39')s deck and the serious differences in the acceleration spectrum at different locations of the deck, in order to select the optimal stiffness, the locations of the desired module must also be considered.

Keywords

• floating platform
• dynamic analysis
• fpso
• time history analysis
• neoprene