National foreword

This British Standard is the UK implementation of ISO 14347:2008.

The UK participation in its preparation was entrusted to Technical Committee WEE/37, Acceptance levels for flaws in welds.

A list of organizations represented on this committee can be obtained on request to its secretary.

This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application.

Compliance with a British Standard cannot confer immunity from legal obligations.

This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 December 2008

Foreword

ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, also take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization.

International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2.

The main task of technical committees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights.

ISO 14347 was prepared by the International Institute of Welding, Commission XV, Design, analysis and fabrication of welded structures, recognized as an international standardizing body in the field of welding in accordance with Council Resolution 42/1999.

Requests for official interpretations of any aspect of this International Standard should be directed to the ISO Central Secretariat, who will forward them to the IIW Secretariat for an official response.

1 Scope

1.1 General

This International Standard gives recommendations for the design and analysis of unstiffened, welded, nodal joints in braced structures composed of hollow sections of circular or square shape (with or without rectangular chord) under fatigue loading.

This International Standard applies to structures:

fulfilling quality requirements for hollow sections (see Annex A);
complying with recommended weld details (see Annex B);
employing permitted steel grades (see 1.2);
having hollow section joints (see 1.3);
having either
1. square or rectangular hollow sections with a thickness between 4 mm and 16 mm, or
2. circular hollow sections with a thickness between 4 mm and 50 mm;
having as stress range the range of “hot-spot” stress;
having identical brace (branch) members.

1.2 Materials

This International Standard applies to both hot-finished and cold-formed steel structural hollow sections, complying with the applicable national manufacturing specification, that fulfil specified quality requirements (see Annex A).

1.3 Types of joints

This International Standard applies to joints consisting of circular hollow sections (CHS) or rectangular hollow sections (RHS) as used in uniplanar or multiplanar trusses or girders, such as T-, Y-, X-, K-, XX-, and KK-joints (see Figure 1 and Figure 2).

2 Normative references

3 Terms and definitions

4 Symbols and abbreviated terms

5 Cumulative fatigue damage

5.1

5.2

5.3

5.4

6 Partial safety factor

6.1

6.2

7 Fatigue design procedures

7.1 Hot-spot stress method

7.2 Design procedures

8 Fatigue strength

8.1 Member forces

8.2 Nominal stress ranges

8.3 SCF calculations

8.4 Hot-spot stress ranges

8.5 Fatigue strength curves

9 SCF calculations for CHS joints

9.1 Uniplanar CHS T- and Y-joints

9.2 Uniplanar CHS X-joints

9.3 Uniplanar CHS K-joints with gap

9.4 Multiplanar CHS XX-joints

9.5 Multiplanar CHS KK-joints with gap

9.6 Minimum SCF values

10 SCF calculations for RHS joints

10.1 Uniplanar RHS T- and X-joints

10.2 Uniplanar RHS K-joints with gap

10.3 Uniplanar RHS K-joints with overlap

10.4 Multiplanar RHS KK-joints with gap

10.5 Minimum SCF values

Bibliography

BS ISO 14347:2008

Fatigue. Design procedure for welded hollow-section joints. Recommendations

Current

Published:

31 Dec 2008