ISO/TC 67/SC 7/WG 7 Site Specific Assessment of MOU’s
Editing / Review Panel
Report on Meeting of 1st 2nd & 4th April 2008
1st - 2nd at Transocean, 15,375 Memorial Drive, Houston, Texas
4th at ABS, 16855 Northchase Drive, Greenspoint, Houston, Texas
Meeting Report by Mike Hoyle
Background and Attendance
The meeting was scheduled during the previous meeting of 15th-18th January, 2008.
The attendees comprised:
Rev 0 - 15th April 2008 Page 1 of 18
Mike Hoyle (Convenor, UK)
Dave Lewis (USA) - not 2nd
Andrea Mangiavacchi (USA) - not 2nd
John Stiff (USA)
Doug Stock (USA)
Rev 0 - 15th April 2008 Page 1 of 18
ISO/TC 67/SC 7/WG 7 Editing / Review Panel. Report on meeting of 1st, 2nd & 4th April 2008
Objectives / Agenda
Per the forward plan from the previous meeting & calling notice of 10th March 2008:
1. Minutes of last meeting.
2. Information Exchange
3. Status of action items last meeting, not otherwise addressed.
4. Confirm changes made after last meeting.
5. Address any initial issues arising from Stage 1 benchmarking
6. Continuation of formal A-Z ISO-speak editing.
7. Forward plan for the next stages of editing.
Meeting Report
1. Minutes of last meeting
1.1. There were no comments on the minutes of the last meeting.
2. Information exchange, etc:
2.1. Debate on Consequence matrix at SC7; SC7 will not allow a different matrix, but we can rely on short-term evaluation of the facilities class. Wrt release of inventory, SC7 are happy that we can have our own requirements, but would like us to explain why we are different. ERP not entirely happy with this.
2.2. Re-arrangement of 19901-4 into 2 documents: ISO 19901-4 addressing marine soil/site investigations and geotechnical interpretation and ISO 19901-8 addressing shallow foundations. There was an attempt by various attendees at the SC7 meeting to bring more information into the 19901-8 document. Mike had strongly resisted the idea of taking jack-up specifics out of 19905-1. ERP noted that the content of 19901-8 might cover mat-rig foundations.
2.3. John advised that Alan Dixon had contacted him to advise that HSE will contribute £15k towards the cost of the benchmarking work.
2.4. The meeting held a telephone discussion with Paul Frieze wrt progressing Clause 12 book keeping, comparison of tubulars in 19902 with 19905-1 & class 2 to 3 transition. John suggested that Paul should contact HSE wrt further funding. Subsequent feedback indicated that this may not be forthcoming, although there may be limited funding for some of the tasks we requested (possibly 2x16 hour jobs).
3. Status of action items last meeting, not otherwise addressed:
3.1. Information exchange (previous 2.1):
Mike had sent latest draft to Houlsby/Cassidy.
3.2. Project funding (previous 3.1):
It appears that Rupert still has the ability to fund, at least, smaller work-items. Doug has still to submit his proposal for testing of the seismic text. The scope is to be developed for agreement at the May P5 meeting. Action: Doug
3.3. Issues re ISO CS (previous 3.2)
Mike has again failed to discuss with ISO CS the presentation of symbols and bibliography by Clause. Andrea had previously advised him to contact Stephen Kennedy. Action: Mike
3.4. Benchmarking (previous 3.3)
It had previously been agreed that the pre-OTC Panel Convenors meeting will review the "problem log" and "suggested changes" from the Phase 1 benchmarking.
Action: Mike
3.5. Actions from meeting proper (previous 3.6):
November meeting actions for P3, P4 & P11 need to be followed up.
Action: Mike & Panels 3, 4 and 11
3.6. Review, and aim to resolve, inputs from the initial Clause 12 benchmarking (Previous4).
Annex A of the Noble Denton report contains comments on the Clause 12 text. This was reviewed in January and actions taken or assigned. The result (taken from January minutes) is shown in Attachment 1. Mike had addressed the outstanding ERP actions remaining after the January meeting. A number of topics are still open pending resolution by P10/PAFA (see highlighted text in Attachment 1). Action: John
3.7. November meeting actions (Previous 6):
Actions from November - carried forward to April
The review of the consistency of usage and definition of "bearing capacity" v/s "available bearing capacity" was carried forward for June. Action: June meeting
The action to switch the usage of F and Q to F=action & Q=capacity remains with P4. All should standardise on this usage. Action: Patrick/P4/All Panels
4. Confirm changes made after last meeting [ and more … … ].
The meeting reviewed, and revised where necessary, Mike's updates:
· From wave-current to wave/current
· From footing to spudcan (where spudcan is correct)
· Replacing of back-fill with back-flow
The meeting also reviewed the usage of site & location and decided that a location is a point in a site - see Clause 6.1. This to be brought to attention of PC meeting.
Action: Mike
It was also decided that:
mode = exploration, workover, etc:
configuration = arrangement of derrick, VDL, etc
situation = configuration + environment
and changes were made accordingly; more may be required. Action: June ERP
The meeting also:
· Reviewed & updated the use of "joint-probability"
· Noted the need to need to standardise on centre (v/c center ) and jackup with hard hyphen. Done by Mike, post meeting.
During the course of these reviews a significant number of edits were made to other areas of the text, and particularly 11.4 / A.11.4. It was noted that P4 input is required to A.11.3.1
Action: Patrick/P4
Also suggested that P4 and P3 should address torsional stiffness of foundation and equivalent leg models. Action: Pao-Lin/P3 & Patrick/P4
5. Address any initial issues arising from Stage 1 benchmarking
Mike advised that the documentation he had received to date has revealed a number of minor items. He suggested that the full review of these be deferred until May and/or the next ERP meeting.
John advised that he had previously produced a draft 'jack-up' primer for ABS. He will see if this can be made more generally available. Action: John
6. Continuation of formal A-Z ISO-speak editing.
The meeting spent time on a lengthy review & several rewrites of the S & C definitions following feedback from SC7 meeting. C1 was re-written several times over the course of the meeting. The text wrt 50yr/100yr and SLS/ULS was also revised. IADC & P11 to be canvassed to ensure these changes do not affect them. It was noted that 19902 use SLS action factor = 0.9*ULS action factor (see their 9.10 & A.9.10.3.2.1).
Action: Dave/ IADC & Gregers/P11
After dealing with the above, the meeting progresses through the Normative from Clause 5 through to the end of Clause 6.
Figure 5.2-1 needs further work & checking of cross-referencing. T0 be done at next meeting by an individual. Action: ANO at next meeting
Suggestion to add an Annex containing draft contents list for a site assessment report.
Action: ANO at next meeting
Noted that the list in 6.5 needs to be checked against other sections.
Action: ANO at next meeting
7. Agree actions items, forward plan and date & subject matter of next meeting
The actions noted above were confirmed. Additionally Mike undertook to update the collation of all the in-text actions in < >, see Attachment 2.
The goals of the June meeting will be:
· Close-out actions from this meeting
· Address Panel inputs from May
· Address general issues that may have emerged from the Phase 1 benchmarking
· Pursue the ISO-speak editing
with the aim of ensuring that the document is as ready for Phase 2 benchmarking as possible, so that Phase 2 can be initiated soon after OTC. Realistically this will not be until July as a)the text will need to be finalised by the June meeting, and b) it is unlikely that the Phase 1 will provide the updated scope until mid or late May.
It had previously been considered likely that the subsequent phases will run past the date scheduled for issue of the DIS in December. Consequently, the DIS may have to be delayed, unless the IADC are sufficiently comfortable with the results from Phase 1. Consequently, it was considered likely that editing the DIS will likely be on-going into 2009.
The schedule of future meetings, starting at 08:30 each day, was agreed as:
June 24th - 27th
September 30th, October 1st and 3rd (round IADC meeting)
Late Fall -To be agreed.
The location for the June meeting was tentatively set as Transocean at Greenway Plaza for the first 3 days and ABS at Greenspoint on the last day.
The draft Agenda for the June meeting is:
1. Minutes of last meeting.
2. Information Exchange
3. Status/close-out of action items from last meeting, not otherwise addressed.
4. Confirm inputs from May panel meetings.
5. Issues from Phase 1 benchmarking.
6. Continuation of formal A-Z ISO-speak editing.
7. Confirmation of actions.
8. Forward plan for the next stages of editing.
9. Epilogue
The panel considered that good progress had been made. Thanks were due to Pharr, the distant host, Dianne and Karen of Transocean and John & Allison of ABS for hosting the meeting.
MJRH 15th April 2008
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ISO/TC 67/SC 7/WG 7 Editing / Review Panel. Report on meeting of 1st, 2nd & 4th April 2008
ATTACHMENT 1
ATTACHMENT 1
Appendix A of ND report with ERP responses - After April ERP meeting
Highlight added April 2008 - where action is still required
A : Notes and Comments on ISO-19905 Clause 12 Sections
Section / Notes and comments / ERP Action/responseGeneral / The equation numbering will be resolved.
Where applicable, we intend to retain references to the source AISC equations, using the latest edition (unless the equation appears only in an older edition).
A.12 / Structural Strength
A.12.1 / Applicability
A.12.1.1 / General
Line 5, grammar, “are include” should be “are including” or “include”
In 3rd para reference is made to the components combined in a typical section. It refers to Table A.12.2-1 as showing examples. The examples shown are typical of chord sections but the diagrams of plastic and elastic stress distribution are clearly more appropriate to building sections where bending is predominantly in one direction. We foresee difficulty in analysing these sections when the neutral axis is likely to be different for each load case considered, - particularly for those elements which are considered as slender. / Deleted "include".
We accept that the approach is difficult. However it needs to be exercised - and Class 3 and 4 results compared to SNAME before we come to a decision.
A.12.1.2 / Truss type legs
A.12.1.3 / Other leg types
A.12.1.4 / Fixation system and/or elevating system
A.12.1.5 / Spudcan strength including connection to the leg
A.12.1.6 / Overview of the assessment procedure
A.12.2 / Classification of member cross-sections
A.12.2.1 / Member type
A.12.2.2 / Material yield strength
Fyeff defined here is not used anywhere else in Clause 12 / Yes, but we intend that it will be used later with full section properties in place of present use of Fymin with Aeff, Seff, etc..
A.12.2.3 / Classification definitions
A.12.2.3.1 / Tubular member classification
A.12.2.3.2 / Prismatic member classification
Equation numbers are missing.
When defining “Internal Components” a distinction is drawn between “flange internal” and “web internal” components. For the purposes of a jack-up chord this is a confusing distinction since bending may occur about any axis through the section.
It is not clear what procedure should be adopted if not all the elements in a section are of the same slenderness class. (but see also A.12.3.1)
The equation supplied to check for need to consider torsional buckling is missing an equation reference number:
Several typical chords do not pass this test and therefore require checking for Lateral Torsional Buckling (LTB) - see notes for Section A.12.6.2.6.
Considering the usual types of chords, as shown in Table A.12.2-1~3, concepts of base plate, side plate, rack plate, split tubular components and stiffeners, etc., may be better than web and flange when used for classification.
In Table A.12.2-1~3, Fy has not been non-dimensionalised and has no units defined (MPa was assumed in the review though)
In Table A.12.2-1~3, stress distribution pattern drawn as I -shaped beam which is difficult to associate with real chords. Moreover, the true stress reacted across the chord section may not be about the major and minor bending axes assumed in Tables and thus very difficult to be used for the classification.
Classification for class 4 - slender section needs to be counted in this section. / Yes - fixed MJRH Jan08.
Noted
See normative 12.2.3 !
Yes - fixed MJRH Jan08..
We agree that a more appropriate check is required.
Noted
To be non-dimensionalised ?by PAFA.
Noted
C4 added to tables.
A.12.2.3.3 / Reinforced components
The illustration under this section (Figure A.12.2-1: “Definitions for reinforced plate”) shows a reinforcement typical for LeTourneau style chords. This is similar to the example of case 1 and allowed the reinforced plate to be classified as an element which placed the whole section into the “Plastic - Class 1” category.
The present requirement is for one check using an effective plate thickness. Checks of typical chords have shown that quite different results occur if the individual elements are considered. Base plate and reinforcing plate may be susceptible to local plate buckling when separated as discussed in the report.
The engineer given this task used the same procedure to take the two chord plates and two web plates found in the case 3 chord (see Error! Reference source not found.) an classified the resulting reinforced plate as “Plastic - Class 1” even though consideration of the individual web plates would have classified the section as “Non-compact - Class 3”. As this may not be the intention of the Clause 12 authors some additional clarification may be required in this part of the document. /
This was the intent
This was the intent.
Text revised to prevent the Hua/Stonor interpretation.
A.12.3 / Section properties