1

Tripartite meetingSeoul, September 2009

Status and Early Experience of CSRs

Kirsi TikkaVice President, Global Technology and

Business Development, ABS

IACS Small Group/CSR Chair

2

Update on CSR

• History of the Common Structural Rules

– Adoption January 2006

– Implementation April 2006

– One year feedback period before developing harmonization plan

– Currently ongoing:• CSR Maintenance

• CSR Harmonization

3

IACS Organisation for CSR

IACS Council

SG/CSR

Hull Panel Project Management TeamCSR Harmonization

CSR Secretariat

Project Teams(Including Cross Check Teams)

Project Teams(Including Development Projects)

Technical review

4

Tripartite meeting Seoul, September 2009

Update on CSR Maintenance

5

Adopted CSR Rule Changes and Corrigenda

Tanker:– Rule Change Notice 1 (Sept

2006)

– Corrigenda 1 (Apr 06)

– Corrigenda 2 (July 06)

– Corrigenda 3 (Nov 2007)

– Rule Change Notice 2 (Feb 2008)

– Corrigenda 1 to the July 2008 edition (June 2008)

– Rule Change Notice 1 to the July 2008 edition (Jan 2009)*

Tankerconsolidated

version1 July 2008

Tankerconsolidated

version1 July 2009*

* Note: Based on further input from industry, IACS Council has decided to postpone the implementation of Rule Change Notice 1 to the July 2008 edition until such time as a technical study is completed.

6

Adopted CSR Rule Changes and Corrigenda

Bulk Carrier:– Corrigenda 1 (May 06)

– Corrigenda 2 (Jan 07)

– Corrigenda 3 (July 07)

– Corrigenda 4 (Sept 07)

– Rule Change Notice 1 (Nov 2007)

– Rule Change Notice 2 (Feb 2008)

– Corrigenda 5 (May 2008)

– Rule Change Notice 3 (12 Sept 2008)

– Rule Change Notice 1 to the July 2008 edition (Jan 2009)

Bulk Carrierconsolidated

version1 July 2008

Bulk Carrierconsolidated

version1 July 2009

7

Current CSR Rule Changes

Tanker:– RCN 1

•Accepted by HP

•1st round of TC and Industry Group review (July – Aug 2008)

•Comments incorporated or addressed by CSR PT2

•2nd round of TC and Industry Group review (Oct – Nov 2008)

•Published January 2009

•Effective date (postponed)

8

Current CSR Rule Changes

Bulk Carrier:– RCN 1

•Accepted by HP

•1st round of TC and Industry Group review (July – Aug 2008)

•Comments incorporated or addressed by CSR PT1

•2nd round of TC and Industry Group review (Oct – Nov 2008)

•Published January 2009

•Effective date 1 July 2009

9

Revision History – Tracking Database

IACS CSR Tracking Database is available on-line

•  Objective

- Provide users with a searchable database on CSR revision history with supporting materials

- Provide users easy and quick access to a full and up-to-date history of a particular requirement

• Test and development:

- It was tested during 2008, and launched to general public as a development version in Nov 2008

- There are now over 60 industry users

• Web link: www.iacs-csrtrack.org.uk

10

Revision History – Tracking Database

• What is published:

- Full History of Revision (Rule Changes and Corrigenda) on a paragraph by paragraph basis;

- Date of approval, what was amended/corrected, Technical Background, implementation date

•  Search Facility

Search and sort out rule change text by Rule Change Notice/Corrigenda No., approval date, or effective date etc.

• Industry and interested users are invited to contact the IACS CSR Secretariat (csr@iacs.org.uk) for log-in IDs and a User Manual.

11

IACS CSR Knowledge Centre (KC) activity

(as of 31 July 2009)

• KC since 1 August 2006 to capture Questions & Answers, Common Interpretations, and Rule Change requests

• 805 entries in the database - 261 relating to the Tanker Rules, 534 to the Bulker Rules and 10 to both sets of Rules

• 724 of the items have been completed (246 tanker, 469 bulker and 9 both)

• 305 items led to a rule change being requested (around 50% editorial changes)

12

Typical CSR Experience / KC activity driving rule changes

• General findings:– Steel weight is generally increased.

• Stiffeners• Web frames• Midship area

– Structural enhancements• Steel placed where needed• Additional criteria applied (S, S+D, Impact, Buckling,

Fatigue, Ultimate strength, Empirical) • Interaction between structural elements

(Plates/Stiffeners)• Enhanced design loads (NA, 25 years, hydrodynamics based)

– Optimization• Designers are becoming more proficient with CSR• Optimizing to rule minimums• Constantly carrying out scantling comparisons with

previously approved designs• Requesting re-review of local requirements that are

“outside the norm”

– Greater % of higher strength steel being proposed

• Provided for local plate increases• Provided for local high stress areas found during

analysis• Buckling and fatigue closely reviewed in way of HTS

13

Typical CSR Experience / KC activity driving rule changes

• General findings (continued):

– Areas for CSR improvement• Tighten up rule minimums• Tighten up rule interpretations• Clarify rules through feedback / Knowledge

Center• Constantly strive to relate requirements to

actual physical phenomena (loads and structural response)

• Reference service history back-up for enhancement to requirements

14

Cross Check Project Status

Prescriptive Rules Cross Check

and

FEA Cross Check

•All 10 IACS members involved

•First phase of the Cross Check for Tanker and Bulk Carrier calculations has been completed

•The results provide a benchmark for the societies to verify their calculation tools

•The results indicate reasonable coherence

•Common interpretations and/or Rule changes will be needed to clarify the application of the Rules

•Additional work will be carried out to cover more ships

15

Tripartite meeting

Update on CSR Harmonization

as of Aug 2009

16

Harmonized Structural Rules for Oil Tankers and Bulk Carriers

•Deliverables

– Common Rules covering Oil tankers and bulk carriers

– 3 booklets:

•Common parts for both types

•Specific part applicable to Oil Tankers

•Specific part applicable to Bulk Carriers

•Preliminary draft issue of complete harmonized rule for stakeholder comment by Dec 2011

•Final draft issue scheduled for mid 2012

17

General Action Plan for CSR Harmonisation

• Items identified at CSR release for long term harmonisation:

– Wave loads

– Fatigue

– Finite element analysis

– Buckling

– Prescriptive requirements

• Comments from ICS:

– Quartering Sea

– Corrosion

– Welding

– FEM analysis

18

Project Teams Established in 2008

HPT 1 Wave Loads

Harmonization of the LoadsIncludes re-examination of the environmental data and quartering sea condition for bulk carriers

HPT 2 Buckling

Harmonization of Buckling calculation methods for prescriptive and FEM

HPT 3 FEAHarmonization of FEM calculation methods

HPT 4 Corrosion

Re-examination of data

HPT 5 Welding

Review of welding requirement especially in way of high stress areas

HPT 6 Fatigue assessment of hatch corners of Bulk Carriers under Quartering Sea for updating CSR BC

19

Project Teams Established in 2009

HPT 7 Ship in Operation Criteria

HPT 8 Fatigue assessment

HPT 9 Prescriptive criteria

Sub group HPT 9.1

Safety criteria and principles

Sub group HPT 9.2

Detailed requirements

20

Project Status

HPT 1 Wave Loads

• Extreme loads (10-8)HS, FS and BS load cases achieved for Accelerations, Hull girder loads, internal & external pressure

• Oblique sea in progress in connection btwn HPT1 & HPT6

• Fatigue loads started

Sub-PT for Re-Examination of the environmental data: 95 % progress

HPT 2 Buckling

Draft text for:

•slenderness requirement,

•prescriptive formulae,

•hull girder buckling stress,

•Stiffeners used as PMA

FEM buckling appraisal in progress

21

Project Status

HPT 3 FEA

The main tasks in progress

•Eccentric beam for modeling

•Requirement of large opening

•Boundary Condition

•Equilibrium Method

•List of Compulsory Details to be analyzed by Fine Mesh Analysis

•Screening Criteria for Fine Mesh Analysis

•Fine Mesh Model Size and Permissible Criteria

22

Project Status

HPT 4 Corrosion

The following have been completed :

•Detailed Background Document for the Harmonized Rules

•Harmonized text for Net Scantling Approach and Corrosion Additions

•Technical Background Document

In progress

•After analysis of the data received from IACS members and ICS, the corrosion additions will be reviewed and possibly updated.

•The harmonized rule text, detailed background and technical background will be updated as appropriate over the next two years to accommodate further input from GBS, analysis of new data and general feedback that is received.

23

Project Status

HPT 5 Welding

• The updated fillet welds scantling comparison

• Draft of HSR fillet weld factors for different structural members

• Preliminary calculation of the impact on existing rules performed

• Preliminary list of “high stress areas” prepared to meet ICS requirements

In progress:

Draft rules and TB

24

Project Status

HPT 6 Fatigue of Hatch Corner under quartering sea in CSR BC

• Two different load-cases with respect to torsion

• Development of new load-cases and application to FE cargo hold models

In progress

• Load generation – Dominant wave states

were identified – Envelope curves for the

torsional moments – Development of EDW and

pressure distribution for the mid-ship area

• Boundary condition for FE cargo hold models

• Load application on FE cargo hold models

• Numerical analysis : Spectral fatigue analyses carried out for a handymax and cape-size vessel

25

Project Status

HPT 7 Ship in Operation

Task 50 finalized under supervision of Survey Panel will be used by HPT7

Work programme approved by Council on 2.6.09

Kick-off meeting in Sept 09

HPT 8 Fatigue

Work programme approved by Council on 2.6.09

Kick-off meeting held on 26-28 Aug 09

CSR Rule comparison started

Preliminary discussion on fatigue load in progress

HPT9

Prescriptive criteria

Work programme approved by Council on 2.6.09

Kick-off meeting held on 16-18.6.09 for the 2 sub groups

CSR Rule comparison started

26

Thank you

Status and Early Experience of CSRs

Kirsi TikkaVice President, Global Technology and

Business Development, ABS

IACS Small Group/CSR Chair