A Comparative Study of the Performance of Top-Tensioned Composite and Steel Risers under Vortex-induced Loading

Abstract

Aker Maritime, Inc., J. J. Murray, Spars International, inc. Copyrwh! 1S9? OfMore l'eshrmlc+w Conference TMs Wprwasvovrcd fw@resemtilw arttw lF.9mi$~c Tetino!~y cotire.cehe!d m Hcuf.mn, TeKas, M Msy 1SW TFUSPWXI W,. s.ktod fo.~<escmtti,onbythe OTC Prqcam COmn7ttteefO!10wmQrewwti infmmaim. cnrdam.d r. . . absk.ci mbmlled by the autkqs) Cotie.ts of the paper, as presentacl. hate not bfmn revrnwed by the CXfshore Tedvmiog, Co"fcrence and are sub,e~to cormckm b, the a.thor(sl, Th.J nate.d, as presented, dces not rwa?ssanly reflect my postion of the CXfdwm Tec+molcgj conference cr & affiim ElectrcAMc repm<ucmx, dtirtbutlon, or S7.wg. ormyp.fl.f thtspaprfwcommarcalpu~o~s 'wrmmc:twwr, mwl w=nf&tie~bhore T&m fogy C.nfermce,s prtib,tRd. Pemtss,.. tompmd-,n~(nt Is res:rtded [o,?nzbstrtiaf not more than allwotds, i!l.stm:imsnwy math cop.d l%. ;bas$aatimusi Cm!a!n CQn$ptcuous acknowl%dg,nmnt nf.h.m md bywimm thn p?$mr was ABSTRACT Current effoms on the rieveloprnerst of cmnposite riser joints have been mainly focused on low-cost manufacturing and failure strength evaluation of tubtbody and joint connection. The effect of material properties, such as structural damping and structural stiffness, on the rismperforrttance under hyirodyxirnic loading, e.g., the Vortex-

Integration of Advanced Material Components to Deepwater Platforms

“…Fiber reinforced polymeric composite materials typically have higher structural damping than the conventional steel riser materials [10]. These higher frequencies should result in improved VIV performance of the composite riser [11]. Figure 5 compares the natural frequency associated with each mode for steel and composite riser configurations at 6,000 ft water depth.…”

Comparative Study of Vortex-Induced Vibration of FRP Composite Risers with Large Length to Diameter Ratio Under Different Environmental Situations

“…Besides the research of mechanical properties of FRP composite materials in seawater, the responses and performances, including load distributions, fatigue, and vortex-induced vibrations (VIVs) of composite risers under environmental and functional loads have also been investigated [12][13][14][15][16][17][18][19][20][21][22][23][24][25]. The improvement of composite risers in performance over a pure metallic mandrel had been proved through a scaled-down test [23].…”

“…More specifically, the structural composite body of the composite riser joint is likely to have an infinite fatigue life [13,14,16], but still may vary depending on the choice of constituent materials and the manufacturing process. In terms of the VIV of composite risers, it is found that the fundamental frequency of a composite riser with the same boundary condition and geometry was higher than that of a steel riser [18] since the composite riser was much lighter and the value was relatively small [13,14]. The structural damping and tension variations were also significant to the VIV of composite risers [13], i.e., higher tension and damping could reduce VIV-induced fatigue [13,17].…”

“…The structural damping and tension variations were also significant to the VIV of composite risers [13], i.e., higher tension and damping could reduce VIV-induced fatigue [13,17]. A. F. Omar et al [18] found that the maximum VIV stresses of a composite riser were much smaller than those of a steel riser, indicating the better fatigue lives of composite risers. Similarly, William Toh et al [25] and L.B.…”

Effects of Different Design Parameters on the Vortex Induced Vibration of FRP Composite Risers Using Grey Relational Analysis

“…Previous studies confirmed that the structural composite body of the composite riser joint was likely to have an infinite fatigue life [14][15][16], but still may vary depending on the choice of constituent materials and manufacturing process. For the vortex induced vibration (VIV) of composite risers, it was found that, in comparison with a steel riser, the natural frequency of a composite riser with same conditions was larger [19] since the weight of composite riser was much smaller, but the value was still relatively small [14,15]. It was also found that larger tension force and higher structural damping reduced VIV-induced fatigue of composite risers [14,20].…”