ISO 14346:2013

INTERNATIONAL ISO
STANDARD 14346
First edition
2013-03-15
Static design procedure for
welded hollow-section joints —
Recommendations
Procédure statique de conception des joints soudés à section creuse —
Recommandations
Reference number
©
ISO 2013
© ISO 2013
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ii © ISO 2013 – All rights reserved

Contents Page
Foreword .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols and abbreviated terms . 2
5 Requirements . 5
6 Materials .12
7 Joint types .13
8 Joint classification .19
9 Limit states design .23
10 Partial load and safety factors for loads and resistances .24
11 Static design procedures .24
11.1 General .24
11.2 Design member forces .24
11.3 Design resistance .24
11.4 Design criteria .25
12 Design member forces .25
12.1 Analysis methods .25
12.2 Design member forces .26
13 Design criteria .26
13.1 Failure modes .26
13.2 Uniplanar joints .26
13.3 Uniplanar overlap joints with a CHS, RHS, I- or H-section chord .28
13.4 Special uniplanar joints .29
13.5 Multiplanar joints .30
14 Design resistance of uniplanar CHS braces to CHS chord joints.30
14.1 Design axial resistance .30
14.2 Design moment resistance.31
15 Design resistance of uniplanar gusset plates, I- or H-section braces or RHS braces to CHS
chord joints .32
16 Design resistance of multiplanar joints with CHS chord .33
17 Design resistance of uniplanar RHS braces or CHS braces to RHS chord joints .34
17.1 Design axial resistance .34
17.2 Design moment resistance.36
18 Design resistance of uniplanar SHS or CHS braces to SHS chord joints .37
18.1 Design axial resistance .37
18.2 Design moment resistance.38
19 Design resistance of uniplanar gusset plate to RHS joints .38
20 Design resistance of multiplanar joints with RHS chord .39
21 Design resistance of uniplanar CHS or RHS braces to I- or H-section chord joints .40
21.1 Design axial resistance .40
21.2 Design moment resistance.42
22 Design resistance of uniplanar overlap joints with a CHS, RHS, I- or H-section chord .42
Annex A (informative) Quality requirements for hollow sections .46
Annex B (informative) Weld details .48
Annex C (informative) Partial safety factors on static strength .50
Bibliography .52
iv © ISO 2013 – All rights reserved

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 14346 was prepared by the International Institute of Welding, which has been approved as an
international standardizing body in the field of welding by the ISO Council.
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.
INTERNATIONAL STANDARD ISO 14346:2013(E)
Static design procedure for welded hollow-section joints —
Recommendations
1 Scope
This International Standard gives guidelines for the design and analysis of welded uniplanar and
multiplanar joints in lattice structures composed of circular (CHS), square (SHS) or rectangular (RHS)
hollow sections, and of uniplanar joints in lattice structures composed of combinations of hollow sections
with open sections under static loading. This International Standard is applicable to CHS or RHS Y-, X-
and K-joints and their multiplanar equivalents, gusset plate to CHS or RHS joints, open-section and RHS
to CHS joints, and hollow-section to open-section joints.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated
references, only the edition cited applies. For undated references, the latest edition of the referenced
document (including any amendments) applies.
ISO 630 (all parts), Structural steels
ISO 14347, Fatigue — Design procedure for welded hollow-section joints — Recommendations
ISO/TR 25901, Welding and related processes — Vocabulary
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 14347, ISO/TR 25901, and the
following apply.
3.1
chord face failure
chord plastification
plastic failure of the chord face or plastic failure of the chord cross-section
3.2
chord punching shear
crack initiation in a hollow-section chord wall leading to rupture of a brace member from the chord member
3.3
chord side wall failure
chord web failure
yielding, crushing or instability (crippling or buckling of the chord side wall or chord web) under the
relevant brace member
3.4
cross-section classification
identification of the extent to which the resistance (to axial compression or bending moment) and
rotation capacity of a cross-section are limited by its local buckling resistance
Note 1 to entry: For example, four classes are given in Eurocode 3 (see EN 1993-1-1) together with three limits on
diameter-to-thickness ratio for CHS or width-to-thickness ratio for RHS.
3.5
joint configuration
type or layout of the joint or joints in a zone within which the axes of two or more interconnected
members or elements intersect
3.6
local chord member yielding
local buckling of the chord connecting face in an overlapped joint
3.7
local yielding of overlapping brace
local yielding of overlapping plate
local yielding of brace
local yielding of plate
cracking in the weld or in a brace member, or local buckling of a brace member with reduced effective width
3.8
multiplanar joint
in a lattice structure, a joint connecting members situated in more than one plane
3.9
structural properties of a joint
resistance to forces and moments in the connected members, deformation and/or rotation capacity
3.10
uniplanar joint
in a lattice structure, a joint connecting members situated in a single plane
4 Symbols and abbreviated terms
A cross-sectional area of member i (i = 0, 1, 2)
i
A shear area of a chord member
s
b effective width of a plate or
...