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INTRODUCTION OF
EUROCODES
In the next seven or eight months
the Eurocodes will be published with National Application Documents;
they will be in use as alternative codes of practice for engineering
design. This transition period will show designers who take the
trouble to read the documents that there are savings to be made in
the structures designed with theses new rules and in some cases they
will highlight shortcomings in or current methods of design.
As designers, we should take
advantage of the transition period to get our Eurocode knowledge up
to the same level as our current knowledge of the extant practices.
The transition period will be surprisingly short when the withdrawal
of the current codes will herald the end of the dual operation and
the beginning of the full application of the Eurocodes.
There are nine main euro codes or
euro norms covering the methods of design and use of the main
materials in structural engineering: -
EN 1990 Eurocode:
Basis of structural design
EN 1991 Eurocode 1:
Actions on structures
EN 1992 Eurocode 2:
Design of concrete structures
EN 1993 Eurocode 3:
Design of steel structures
EN 1994 Eurocode 4:
Design of composite steel and concrete structures
EN 1995 Eurocode 5:
Design of timber structures
EN 1996 Eurocode 6:
Design of masonry structures
EN 1997 Eurocode 7:
Geotechnical design
EN 1998 Eurocode 8:
Design of structures for earthquake resistance
EN 1999 Eurocode 9:
Design of aluminium structures
A designer will have to make
reference to several of these codes to gather the rules for a
particular structure because the philosophy of the arrangement of
the text is to eliminate duplication; each code only carries rules
for the specific area of design featured in the title and makes
reference back the other codes such as EN 1990 where basic rules are
defined. For instance, EN 1994 refers the designer to EN 1993 for
steel and EN 1992 for concrete rules. Composite action is not
covered in EN 1992 or EN 1993 except by reference to EN 1994.
Each code has been sub divided
into parts and sections with greater detail for particular aspects
of design in the scope of the code. For example, the material codes
2 to 6 and 9 each have a part covering fire resistance for those
materials, but each in turn refers back to EN 1991, which covers the
basic aspects of the actions of fire on structures as well as the
permanent, transient and variable loads that are used for all
materials.
New words and terminology have
been adopted in the text that are scientifically and grammatically
correct, without ambiguity in each of the three main languages,
English, French and German, of the European community.
This is a significant
harmonisation of engineering knowledge, incorporating as it does the
very latest proven technology for the structural designer. Whilst
general agreement has been reached on the vast majority of factors
and characteristic values to be used with the rules of design, some
variation between nations has been permitted to account for regional
variations in climate and working practices. These variations are
held in the National Application Document for each code; any design
for a specific country must be made using not only the rules in the
relevant Euro norm but using also the variations permitted in the
appropriate National Application Document. A French designer of a
structure to be erected in Ireland may use the Eurocode published by
the French Standards Authority (AFNOR) but the designer must use the
variations required by the appropriate National Application Document
for Ireland published by the National Standards Authority of Ireland
(NSAI).
You may already have noted that
many supporting standards for the production, testing and
installation of products have recently been published, these are
required ahead of the design rules to ensure that these supporting
standards are in place before the design rules are implemented in
each of the European Countries.
Like the Euro, the introduction
of the design Euro Norms will be sensibly almost on the same day;
they must be published within six months of the date of
availability.
Colin Short, Colin Short Associates | 
