scope:

This Standard sets out minimum requirements for the design, fabrication, erection, and modification of steelwork in structures in accordance with the limit state design method (sections 1-17, Appendices A-N) or in accordance with the alternative design method (Appendix P).

Designers using this Standard for the alternative design method must do so only as directed by Appendix P.

This Standard applies to buildings, structures and cranes constructed of steel or of composite steel and concrete members (in accordance with section 13).

This Standard applies to road, rail and pedestrian bridges. Derivation of loads for such bridges shall be to 3.2.1.

Where appropriate specific member design provisions are available for specialised steel structures, these provisions may be used in lieu of the member design provisions of this Standard, provided that the requirements of section 3 are complied with. The factor of safety against failure shall be consistent with that required for ultimate limit state design in accordance with this Standard and the Loadings Standard.

This Standard does not apply to the following structures and materials:

(a) Steel elements less than 3 mm thick, except for packers and square or rectangular hollow sections to 2.2.1(a), (b) or (c).

(b) Steel members for which the value of the yield stress used in design (fy) exceeds 450 MPa. An exception is the use of quenched and tempered steel for which fy = 690 MPa. This steel may be used as splice cover plates, in fully bolted connections only, within the scope of this Standard, provided the bearing stress is limited as specified in 9.3.2.4.2, and the appropriate grade for general structural use is selected (ASTM A514 or equivalent grade). Any welding of such steel shall be in accordance with AS/NZS 1554.4 with regard to any reduction in mechanical properties due to the fabrication process.

(c) Cold-formed members, other than those complying with the appropriate standard from 2.2.1, which shall be designed in accordance with AS/NZS 4600.

Use of this Standard as a means of compliance with the New Zealand Building Code

Part 1 of this Standard will be called up as a verification method for compliance with the New Zealand Building Code in Approved Documents B1: Structure-General, B2: Durability and C4: Structural Stability in Fire.

For use as a verification method in Approved Document B1, Part 1 of this Standard must be used in conjunction with NZS 4203.

Use of Part 1 of this Standard for design of structures which are outside the scope of AS/NZS 1170.0 clauses 1.1 and 1.2, such as those based on special studies or those relying on other loadings documents, comprises an alternative solution and compliance with the Building Code shall be demonstrated.

The Commentary to this Standard, i.e. NZS 3404:Part 2:1997, does not contain requirements essential for compliance with this Standard but fulfils the following roles:

(a) It provides guidance on the use of Part 1;

(b) It summarizes the technical background to the provisions of Part 1;

(c) Wherever Part 1 specifies the use of appropriate or rational design procedures or member design provisions, Part 2 provides details which satisfy the intent of Part 1, either directly or by reference to relevant published documents.

Where Part 1 of this Standard contains provisions that are expressed in non-specific or unquantified terms (such as the required use of appropriate or rational design procedures or member design provisions) then these do not form part of the verification method and must be treated as an alternative solution.

In such instances, note the role of Part 2 in providing guidance (see 1.1.5.4(c)).

Notes in Part 1 have the same status as the clauses, tables or figures to which they refer.