1、 ABSGUIDE FOR BUCKLING AND ULTIMATE STRENGTH ASSESSMENT FOR OFFSHORE STRUCTURES .2004 1 GUIDE FOR BUCKLING AND ULTIMATE STRENGTH ASSESSMENT FOR OFFSHORE STRUCTURES APRIL 2004 NOTICE NO. 1 November 2011 The following Rule Changes become EFFECTIVE AS OF 1 NOVEMBER 2011. (See http:/www.eagle.org for th
2、e consolidated version of the Guide for Buckling and Ultimate Strength Assessment for Offshore Structures 2004, with all Notices and Corrigenda incorporated.) Notes - The date in the parentheses means the date that the Rule becomes effective for new construction based on the contract date for constr
3、uction. (See 1-1-4/3.3 of the ABS Rules for Conditions of Classification Offshore Units and Structures (Part 1).) SECTION 3 PLATES, STIFFENED PANELS AND CORRUGATED PANELS 5 Stiffened Panels (Add new Paragraph 3/5.7, as follows.) 5.7 Overall Buckling State Limit (1 November 2011) The overall buckling
4、 strength of the entire stiffened panels is to satisfy the following equation with respect to the biaxial compression: 22+GyyGxx 1 where x= calculated average compressive stress in the longitudinal direction, in N/cm2(kgf/cm2, lbf/in2) y= calculated average compressive stress in the transverse direc
5、tion, in N/cm2(kgf/cm2, lbf/in2) Gx= critical buckling stress for uniaxial compression in the longitudinal direction, in N/cm2(kgf/cm2, lbf/in2) = ()0000if11ifrExExrrrExExPPPPNotice No. 1 November 2011 2 ABSGUIDE FOR BUCKLING AND ULTIMATE STRENGTH ASSESSMENT FOR OFFSHORE STRUCTURES .2004 Gy= critica
6、l buckling stress for uniaxial compression in the transverse direction, in N/cm2(kgf/cm2, lbf/in2) = ()0000if11ifrEyEyrrrEyEyPPPPEx= elastic buckling stress in the longitudinal direction, in N/cm2(kgf/cm2, lbf/in2) = kx2(DxDy)1/2/(txb2) Ey= elastic buckling stress in the transverse direction, in N/c
7、m2(kgf/cm2, lbf/in2) = ky2(DxDy)1/2/(tyl2) kx= 4 for l/b 1 = 21x+2 + 2x for l/b 1 ky= 4 for b/l 1 = 21y+2 + 2y for b/l 1 x= (l/b)(Dy/Dx)1/4y= (b/l)(Dx/Dy)1/4Dx= EIx/sx(1 2) Dy= EIy/sy(1 2) = Et3/12(1 2) if no stiffener in the transverse direction = (IpxIpy)/(IxIy)1/2t = thickness of the plate, in cm
8、 (in.) l, b = length and width of stiffened panel, respectively, in cm (in.) tx,ty= equivalent thickness of the plate and stiffener in the longitudinal and transverse direction, respectively, in cm (in.) = (sxt + Asx)/sxor (syt + Asy)/sy sx,sy= spacing of stiffeners and girders, respectively, in cm
9、(in.) Asx,Asy= sectional area of stiffeners and girders, excluding the associated plate , respectively, in cm (in.) Ipx,Ipy= moment of inertia of the effective plate alone about the neutral axis of the combined cross section, including stiffener and plate, in cm4(in4) Ix,Iy= moment of inertia of the
10、 stiffener with effective plate in the longitudinal or transverse direction, respectively, in cm4(in4). If no stiffener, the moment of inertia is calculated for the plate only. E = modulus of elasticity, 2.06 107N/cm2(2.1 106kgf/cm2, 30 106lbf/in2) for steel = Poissons ratio, 0.3 for steel Pr= proportional linear elastic limit of the structure, which may be taken as 0.6 for steel 0= specified minimum yield point of the material, in N/cm2(kgf/cm2, lbf/in2) = maximum allowable strength utilization factor, as defined in Subsection 1/11 and 3/1.7
