Engineering Know-How: Lessons from Earthquakes and Rules for Seismic Design - Dynamic Behavior of Concrete and Seismic Engineering - page 337

direct concern of Eurocode 8 (EN 1998) which deals with different types of building
in earthquake areas and comprises six parts. Parts 1 [COL 03b] and 5 are needed to
design buildings; they cover about the same scope as the PS 92 rules. Several
Eurocodes are generally necessary for the complete definition of a reinforced
concrete construction work: EN 1990 gives the general philosophy and operation
combinations, EN 1991 defines the operations to take into account in addition to
earthquakes, EN 1992 [COL 03a] gives common design rules for reinforced
concrete, EN 1998 introduces the action of earthquakes and the additional
arrangements needed in a seismic situation, whilst EN 1997 deals exclusively with
foundations.
The PS 92 standard will still apply in parallel with Eurocode 8 (co-existence
period), probably up to about 2010; the national standard will then disappear, and
will be replaced by the European standard. The general structure and the main
layouts of both standards are quite close, which should make passing from one to the
other easier, despite the greater complexity of Eurocode 8.
As far as anti-seismic construction is concerned, standardization has a strong
status in France [BET 97]. In fact, lawmakers made anti-seismic protection
compulsory, by introducing the 22 July 1987 law (Article 41) and the 2 February
1995 law (the so-called Barnier law). Whereas only new constructions were affected
by the first law, the second expanded the protection to existing facilities, which
raised technical and economic problems, because many existing housing types were
non-compliant. The different orders and decrees specifying how these laws should
be enforced defined seismic zoning in France, classified different constructions
according to their importance with regard to public safety, and fixed standards and
other technical rules.
9.3.2. Main objectives of anti-seismic protection
Because of the violent dynamic features of seismic action and the inaccurate
knowledge we have about its likely effects, building in seismic areas involves
additional efforts in terms of design and construction quality. The anti-seismic
standards give recommendations that complement other design standards; in fact,
constructions must at least respect the objectives of strength, practicality and
durability set for constructions in non-seismic situations and that are subjected to
these other standards (especially Eurocode 2 in the case of reinforced concrete
structures). However, some Eurocode 8 verifying rules are more restrictive than
those in Eurocode 2, and a well-informed designer can limit the number of
verifications required. The goals of Eurocode 8 should be considered besides the
goals of Eurocodes, and both lie within the framework of EN 1990, which describes
the basics of Eurocode design.