1、 GUIDE FOR BUILDING AND CLASSING DRILLSHIPS AUGUST 2011 NOTICE NO. 4 January 2018 The following Changes were approved by the ABS Rules Committee on 30 May 2017 and become EFFECTIVE AS OF 1 JANUARY 2018. (See http:/www.eagle.org for the consolidated version of the Guide for Building and Classing Dril
2、lships, 2011 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 construction, unless otherwise noted. (See 1-1-4/3.3 of the ABS Rules for Conditions of Classification Of
3、fshore Units and Structures (Part 1).) APPENDIX 2 FATIGUE STRENGTH ASSESSMENT OF DRILLSHIPS (Revise Appendix 2, Figure 1, as follows:) FIGURE 1 (continued) Basic Design S-N Curves (2018) Notes (For Appendix 2, Figure 1) (2018) a) Basic design S-N curves S-N curves represent the relationship between
4、the applied stress range (SB) and the number of cycles (N) to failure under the stress range. The basic design curves consist of bi-linear relationships between log(SB) and log(N). They are based upon a statistical analysis of appropriate experimental data and may be taken to represent two standard
5、deviations below the mean line. The first segment of the S-N curve is for N 107and is of the form: log(N) = log(K2) m log(SB) where log(K2) = log(K1) 2 N is the predicted number of cycles to failure under stress range SB; K1is a constant relating to the mean S-N curve; is the standard deviation of l
6、og N; m is the inverse slope of the S-N curve. K2is a constant relating to the first segment of the S-N curve. ABSGUIDE FOR BUILDING AND CLASSING DRILLSHIPS .2011 1 Notice No. 4 January 2018 The second segment of the S-N curve is for N 107and is of the form: log(N) = log(K3) (m + 2) log(SB) where lo
7、g(K3) = log(K2) 2 log(fq) K3is a constant relating to the second segment of the S-N curve; fqis the stress range at the intersection of the two segments of the S-N curve. The relevant values of these terms are shown in the table below. The S-N curves have a change of inverse slope from m to m + 2 at
8、 N = 107cycles. Details of basic S-N curves Class K1 m K2 fq (N/mm2) K3 B 2.343 10150.1821 4.0 1.013 1015100.321 1.019 1019C 1.082 10140.2041 3.5 4.227 101378.190 2.584 1017 D 3.988 10120.2095 3.0 1.520 101253.364 4.328 1015 E 3.289 10120.2509 3.0 1.036 101246.963 2.284 1015F 1.726 10120.2183 3.0 0.632 101239.824 1.002 1015F2 1.231 10120.2279 3.0 0.431 101235.061 0.530 1015G 0.566 10120.1793 3.0 0.248 101229.157 0.211 1015W 0.368 10120.1846 3.0 0.157 101225.054 0.987 10142 ABSGUIDE FOR BUILDING AND CLASSING DRILLSHIPS .2011
