SIST EN 1998-2:2006/A1:2009

Eurocode 8: Design of structures for earthquake resistance - Part 2: Bridges

(1)   The scope of Eurocode 8 is defined in EN 1998-1:2004, 1.1.1 and the scope of this Standard is defined in 1.1.1. Additional parts of Eurocode 8 are indicated in EN 1998-1:2004, 1.1.3.
(2)   Within the framework of the scope set forth in EN 1998-1:2004, this part of the Standard contains the particular Performance Requirements, Compliance Criteria and Application Rules applicable to the design of earthquake resistant bridges.
(3)   This Part primarily covers the seismic design of bridges in which the horizontal seismic actions are mainly resisted through bending of the piers or at the abutments; i.e. of bridges composed of vertical or nearly vertical pier systems supporting the traffic deck superstructure. It is also applicable to the seismic design of cable-stayed and arched bridges, although its provisions should not be considered as fully covering these cases.
(4)   Suspension bridges, timber and masonry bridges, moveable bridges and floating bridges are not included in the scope of this Part.
(5)   This Part contains only those provisions that, in addition to other relevant Eurocodes or relevant Parts of EN 1998, should be observed for the design of bridges in seismic regions. In cases of low seismicity, simplified design criteria may be established (see 2.3.7(1)).
(6)   The following topics are dealt with in the text of this Part:
Basic requirements and Compliance Criteria,
Seismic Action,
Analysis,
Strength Verification,
Detailing.
This Part also includes a special section on seismic isolation with provisions covering the application of this method of seismic protection to bridges.
(7)   Annex G contains rules for the calculation of capacity design effects.
(8)   Annex J contains rules regarding the variation of design properties of seismic isolator units and how such variation may be taken into account in design.

Eurocode 8: Auslegung von Bauwerken gegen Erdbeben - Teil 2: Brücken

Eurocode 8: Calcul des structures pour leur résistance aux séismes - Partie 2: Ponts

No scope available.

Evrokod 8: Projektiranje konstrukcij na potresnih območjih - 2. del: Mostovi

Področje uporabe Evrokoda 8 je opredeljeno v EN 1998-1:2004, 1.1.1 in področje uporabe tega standarda je opredeljeno v 1.1.1. Dodatni deli Evrokoda 8 so navedeni v EN 1998-1:2004, 1.1.3. (2) V okviru področja, opredeljenega v EN 1998-1:2004, ta del standarda vsebuje posebne Zahteve za zmogljivost, Merila skladnosti in Pravila uporabe, ki se uporabljajo za načrtovanje potresno odpornih mostov. (3) Ta del zajema zlasti potresno načrtovanje mostov, kjer se odpornost proti horizontalnim potresnim vplivom doseže predvsem z ukrivljanjem podmostnikov ali pri opornikih; tj. mostov, ki jih tvorijo navpični ali skoraj navpični sistemi podmostnikov, ki podpirajo krov prometne nadgradnje. Uporablja se tudi za potresno načrtovanje mostov s poševnimi zategami in obokanih mostov, čeprav njegove določbe teh primerov ne pokrivajo v celoti. (4) Viseči mostovi, leseni in zidani mostovi, premični mostovi in plavajoči mostovi niso vključeni v področje tega dela standarda. (5) Ta del vsebuje samo tiste določbe, ki jih je poleg drugih pomembnih Evrokodov ali pomembnih delov EN 1998 treba upoštevati pri načrtovanju mostov v potresnih regijah. V primerih nizke potresnosti se smejo vzpostaviti poenostavljena merila načrtovanja (glej 2.3.7(1)). (6) V besedilu tega dela so obravnavane naslednje teme: - Osnovne zahteve in Merila Skladnosti, - Potresni vpliv, - Analiza, - Preverjanje trdnosti, - Podrobno navajanje. Ta del prav tako zajema poseben razdelek o potresni osamitvi z določbami, ki zajemajo uporabo te metode potresne zaščite za mostove. (7) Dodatek G vsebuje pravila za izračun učinkov načrtovanja nosilnosti. (8) Dodatek J vsebuje pravila glede odstopanja lastnosti pri načrtovanju enot potresnih izolatorjev in kako je takšna odstopanja mogoče upoštevati pri načrtovanju.

General Information

• Status: Published
• Public Enquiry End Date: 29-Nov-2008
• Publication Date: 04-May-2009
• ICS: 91.120.25 - Seismic and vibration protection
• ICS: 93.040 - Bridge construction
• Technical Committee: KON - Structures
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 25-Mar-2009
• Due Date: 30-May-2009
• Completion Date: 05-May-2009
• Directive: 89/106/EEC - Construction products
• Directive: TP001 - Pravilnik o mehanski odpornosti in stabilnosti objektov
• Directive: TP237 - Pravilnik o spodnjem ustroju železniških prog
• Mandate: M/265 - Mandate to CEN for the conversion of the Eurocodes from ENV into EN concerning the structural and geotechnical design of buildings and civil engineering works
• Ref Project: EN 1998-2:2005/A1:2009 - Eurocode 8: Design of structures for earthquake resistance - Part 2: Bridges

Relations

• Amends: SIST EN 1998-2:2006 - Eurocode 8 - Design of structures for earthquake resistance - Part 2: Bridges
• Effective Date: 01-Jun-2009

Standards Content (Sample)

SLOVENSKI STANDARD
SIST EN 1998-2:2006/A1:2009
01-junij-2009
(YURNRG3URMHNWLUDQMHNRQVWUXNFLMQDSRWUHVQLKREPRþMLKGHO0RVWRYL
Eurocode 8: Design of structures for earthquake resistance - Part 2: Bridges
Eurocode 8: Auslegung von Bauwerken gegen Erdbeben - Teil 2: Brücken
Eurocode 8: Calcul des structures pour leur résistance aux séismes - Partie 2: Ponts
Ta slovenski standard je istoveten z: EN 1998-2:2005/A1:2009
ICS:
91.120.25 =DãþLWDSUHGSRWUHVLLQ Seismic and vibration
YLEUDFLMDPL protection
93.040 Gradnja mostov Bridge construction
SIST EN 1998-2:2006/A1:2009 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 1998-2:2006/A1:2009

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SIST EN 1998-2:2006/A1:2009
EUROPEAN STANDARD
EN 1998-2:2005/A1
NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2009
ICS 91.120.25; 93.040
English Version
Eurocode 8: Design of structures for earthquake resistance -
Part 2: Bridges
Eurocode 8: Calcul des structures pour leur résistance aux Eurocode 8: Auslegung von Bauwerken gegen Erdbeben -
séismes - Partie 2: Ponts Teil 2: Brücken
This amendment A1 modifies the European Standard EN 1998-2:2005; it was approved by CEN on 12 February 2009.
CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of this
amendment into the relevant national standard without any alteration. Up-to-date lists and bibliographical references concerning such
national standards may be obtained on application to the CEN Management Centre or to any CEN member.
This amendment exists in three official versions (English, French, German). A version in any other language made by translation under the
responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same status as the official
versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: Avenue Marnix 17, B-1000 Brussels
© 2009 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 1998-2:2005/A1:2009: E
worldwide for CEN national Members.

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SIST EN 1998-2:2006/A1:2009
EN 1998-2:2005/A1:2009 (E)
Foreword

This document (EN 1998-2:2005/A1:2009) has been prepared by Technical Committee CEN/TC 250
"Structural Eurocodes", the secretariat of which is held by BSI.
This Amendment to the European Standard EN 1998-2:2005 shall be given the status of a national
standard, either by publication of an identical text or by endorsement, at the latest by September 2009,
and conflicting national standards shall be withdrawn at the latest by March 2010.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CEN [and/or CENELEC] shall not be held responsible for identifying any or all such patent
rights.
According to the CEN/CENELEC Internal Regulations, the national standards organizations of the
following countries are bound to implement this European Standard: Austria, Belgium, Bulgaria, Cyprus,
Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia,
Slovenia, Spain, Sweden, Switzerland and United Kingdom.
2

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SIST EN 1998-2:2006/A1:2009
EN 1998-2:2005/A1:2009 (E)

1) In 1.6.6 Further symbols used in Section 7 and Annexes J, JJ and K of EN 1998-2
Add:
d maximum total displacement of each isolator unit i
m,i
d offset displacement of isolator i
G,i

2) In 7.5.2.4 Variability of properties of the isolator units
Replace (5) and (6) by:
(5) The nominal design properties of simple low-damping elastomeric bearings in accordance
with 7.5.2.3.3(5) and (6), may be assumed as follows:
− Shear modulus  G = α G
b g
NOTE: The value of α typically ranges from 1,1 to 1,4. The appropriate value is best determined by
testing of the device.
− where G is the value of the “apparent conventional shear modulus” in accordance with EN
g
1337-3:2005;
− Equivalent viscous damping ξ = 0,05
eff
(6) The variability of the design properties of simple low-damping elastomeric bearings, due
to ageing and temperature, may be limited to the value of G and assumed as follows:
b
− LBDPs G = G
b,min b
− UBDPs depend on the “minimum bearing temperature for seismic design” T (see J.1(2))
min,b
as follows:
o
- when T ≥ 0 C
min,b
G = 1,2 G
b,max b
o
- when T < 0 C
min,b
the value of G should correspond to T .
b,max min,b
o
NOTE: In the absence of relevant test results, the G value for T < 0 C may be obtained from G
b,max min,b b
adjusted regarding temperature and ageing in accordance with the λ values corresponding to K , specified in
max p
Tables JJ.1 and JJ.2.
3) In 7.5.4 Fundamental mode spectrum analysis
Replace (3) by:
(3) This leads to the results shown in Table 7.1 and Figure 7.4.
3

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SIST EN 1998-2:2006/A1:2009
EN 1998-2:2005/A1:2009 (E)
Table 7.1: Spectral acceleration S and design displacement d
e cd
T S d
eff e cd
T T
C eff
2,5 a Sη d
g eff C
T ≤ T < T
C eff D
T T
eff C
T T T
C D D
2,5 α Sη d
T ≤ T ≤ 4 s C
g
D eff eff
2
T T
eff C
where:
a = γ a (7.7)
g I g,R
and
0,625
2
d = a Sη T (7.8)
C eff C
2 g
π
The value of η should be taken from the expression
eff
0,10
η = ≥ 0,40 (7.9)
eff
0,05+ξ
eff

Maximum shear force
V = M S = K d (7.10)
d d e
eff cd
where:
S, T and T are parameters of the design spectrum depending on the ground type, in
C D
accordance with 7.4.1(1)P and EN 1998-1:2004, 3.2.2.2;
a is the design ground acceleration on type A ground corresponding to the importance
g
category of the bridge;
γ is the importance factor of the bridge; and
I
a is the reference design ground acceleration (corresponding to the reference return period).
g,R

Figure 7.4: Acceleration and displacement spectra
NOTE 1: The elastic response spectrum in EN 1998-1:2004, 3.2.2.2(1)P applies up to periods of 4 s. For
values of T longer than 4 s the elastic displacement response spectrum in EN 1998-1:2004, Annex A may
eff
be used and the elastic acceleration response spectrum may be derived from the elastic displacement
response spectrum by inverting expression (3.7) in EN 1998-1:2004. Nonetheless, isolated bridges with T
eff
> 4 s deserve special attention, due to their inherently low stiffness against any horizontal action.
4

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SIST EN 1998-2:2006/A1:2009
EN 1998-2:2005/A1:2009 (E)
NOTE 2: For a pier of height H with a displacement stiffness K (kN/m), supported by a foundation with
i si
translation stiffness K (kN/m), rotation stiffness K (kNm/rad), and carrying isolator unit i with effective
ti fi
stiffness K (kN/m), the composite stiffness K is (see Figure 7.5N):
bi eff,i
2
1 1 1 H
1
i
= + + + (7.11N)
K
K K K K
eff,i bi si fi
ti
F
i
The flexibility of the isolator and its relative displacement d = typically is much larger than the other
bi
K
bi
components of the superstructure displacement. For this reason the effective damping of the system depends
only on the sum of dissipated energies of the isolators, ΣE , and the relative displacement of the isolator is
Di
practically equal to the displacement of the superstructure at this point (d /d = K /K ≅ 1).
bi id eff,i bi


Key
A – Superstructure
B – Isolator i
C – Pier i
Figure 7.5N: Composite stiffness of pier and isolator i

4) In 7.6.2 Isolating system
Replace (1)P to (5) by:
(1)P The required increased reliability of the isolating system (see 7.3(4)P) shall be
implemented by designing each isolator i for increased design displacements d :
bi,a
d = γ d (7.19)
bi,a IS bi,d
where γ is an amplification factor that is applied only on the design seismic displacement d of
IS bi,d
each isolator i resulting from one of the procedures specified in 7.5.
5

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SIST EN 1998-2:2006/A1:2009
EN 1998-2:2005/A1:2009 (E)
If the spatial variability of the seismic action is accounted for through the simplified method of
3.3(4), (5), (6) and (7)P, the increased design displacements shall be estimated by application of
the rule of 3.3(7)P, where the displacements d due the inertia response determined in
bi,d
accordance with one of the methods in 7.5 shall be amplified in accordance with expression
(7.19) above, while those corresponding to the spatial variability determined in accordance with
3.3.(5) and (6), need not be amplified.
NOTE The value ascribed to γ for use in a country may be defined in its National Annex. The
IS
recommended value is γ = 1,50.
IS
(2)P The maximum total displacement of each isolator unit in each direction d shall be
m,i
verified from expression (7.19a) by adding to the above increased design seismic displacement,
the offset displacement d potentially induced by:
G,i
a) the permanent actions;
b) the long-term deformat
...

SLOVENSKI STANDARD
SIST EN 1998-2:2006/kprA1:2008
01-november-2008
(YURNRG3URMHNWLUDQMHNRQVWUXNFLMQDSRWUHVQLKREPRþMLKGHO0RVWRYL
Eurocode 8: Design of structures for earthquake resistance - Part 2: Bridges
Eurocode 8: Auslegung von Bauwerken gegen Erdbeben - Teil 2: Brücken
Eurocode 8: Calcul des structures pour leur résistance aux séismes - Partie 2: Ponts
Ta slovenski standard je istoveten z: EN 1998-2:2005/prA1
ICS:
91.120.25 =DãþLWDSUHGSRWUHVLLQ Seismic and vibration
YLEUDFLMDPL protection
93.040 Gradnja mostov Bridge construction
SIST EN 1998-2:2006/kprA1:2008 en,fr,de
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

---------------------- Page: 1 ----------------------
SIST EN 1998-2:2006/kprA1:2008

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SIST EN 1998-2:2006/kprA1:2008
EUROPEAN STANDARD
FINAL DRAFT
EN 1998-2:2005
NORME EUROPÉENNE
EUROPÄISCHE NORM
prA1
September 2008
ICS 91.120.25; 93.040

English Version
Eurocode 8: Design of structures for earthquake resistance -
Part 2: Bridges
Eurocode 8: Calcul des structures pour leur résistance aux Eurocode 8: Auslegung von Bauwerken gegen Erdbeben -
séismes - Partie 2: Ponts Teil 2: Brücken
This draft amendment is submitted to CEN members for unique acceptance procedure. It has been drawn up by the Technical Committee
CEN/TC 250.
This draft amendment A1, if approved, will modify the European Standard EN 1998-2:2005. If this draft becomes an amendment, CEN
members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for inclusion of this amendment
into the relevant national standard without any alteration.
This draft amendment was established by CEN in three official versions (English, French, German). A version in any other language made
by translation under the responsibility of a CEN member into its own language and notified to the CEN Management Centre has the same
status as the official versions.
CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Cyprus, Czech Republic, Denmark, Estonia, Finland,
France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal,
Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and United Kingdom.
Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.
EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION
EUROPÄISCHES KOMITEE FÜR NORMUNG
Management Centre: rue de Stassart, 36  B-1050 Brussels
© 2008 CEN All rights of exploitation in any form and by any means reserved Ref. No. EN 1998-2:2005/prA1:2008: E
worldwide for CEN national Members.

---------------------- Page: 3 ----------------------
SIST EN 1998-2:2006/kprA1:2008
EN 1998-2:2005/prA1:2008 (E)
Foreword

This document (EN 1998-2:2005/prA1:2008) has been prepared by Technical Committee CEN/TC 250
"Structural Eurocodes", the secretariat of which is held by BSI.
This document is currently submitted to the Unique Acceptance Procedure.

2

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SIST EN 1998-2:2006/kprA1:2008
EN 1998-2:2005/prA1:2008 (E)

1) In 1.6.6 Further symbols used in Section 7 and Annexes J, JJ and K of EN 1998-2
Add:
d maximum total displacement of each isolator unit i
m,i
d Offset displacement of isolator i
G,i

2) In 7.5.2.4 Variability of properties of the isolator units
Replace (5) and (6) by:
(5) The nominal design properties of simple low-damping elastomeric bearings in accordance
with 7.5.2.3.3(5) and (6), may be assumed as follows:
− Shear modulus  G = α G
b g
NOTE: The value of α typically ranges from 1,1 to 1,4. The appropriate value is best determined by
testing of the device.
− where G is the value of the “apparent conventional shear modulus” in accordance with EN
g
1337-3:2005;
− Equivalent viscous damping ξ = 0,05
eff
(6) The variability of the design properties of simple low-damping elastomeric bearings, due
to ageing and temperature, may be limited to the value of G and assumed as follows:
b
− LBDPs G = G
b,min b
− UBDPs depend on the “minimum bearing temperature for seismic design” T (see J.1(2))
min,b
as follows:
o
- when T ≥ 0 C
min,b
G = 1,2 G
b,max b
o
- when T < 0 C
min,b
the value of G should correspond to T .
b,max min,b
o
NOTE: In the absence of relevant test results, the G value for T < 0 C may be obtained from G
b,max min,b b
adjusted regarding temperature and ageing in accordance with the λ values corresponding to K , specified in
max p
Tables JJ.1 and JJ.2.

3) In 7.5.4 Fundamental mode spectrum analysis
Replace (3) by:
3

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SIST EN 1998-2:2006/kprA1:2008
EN 1998-2:2005/prA1:2008 (E)
(3) This leads to the results shown in Table 7.1 and Figure 7.4.
Table 7.1: Spectral acceleration S and design displacement d
e cd
T S d
eff e cd
T T
C eff
2,5 a Sη d
T ≤ T < T g eff C
C eff D
T T
eff C
T T T
C D D
2,5 α Sη d
T ≤ T ≤ 4 s C
D eff g eff
2
T
T
eff C
where:
a = γ a (7.7)
g I g,R
and
0,625
2
d = a Sη T (7.8)
C eff C
2 g
π
The value of η should be taken from the expression
eff
0,10
η = ≥ 0,40 (7.9)
eff
0,05+ξ
eff

Maximum shear force
V = M S = K d (7.10)
e
d d
eff cd
where:
S, T and T are parameters of the design spectrum depending on the ground type, in
C D
accordance with 7.4.1(1)P and EN 1998-1:2004, 3.2.2.2;
a is the design ground acceleration on type A ground corresponding to the importance
g
category of the bridge;
γ is the importance factor of the bridge; and
I
a is the reference design ground acceleration (corresponding to the reference return period).
g,R

Figure 7.4: Acceleration and displacement spectra
NOTE 1: The elastic response spectrum in EN 1998-1:2004, 3.2.2.2(1)P applies up to periods of 4 s. For
values of T longer than 4 s the elastic displacement response spectrum in EN 1998-1:2004, Annex A may
eff
be used and the elastic acceleration response spectrum may be derived from the elastic displacement
4

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SIST EN 1998-2:2006/kprA1:2008
EN 1998-2:2005/prA1:2008 (E)
response spectrum by inverting expression (3.7) in EN 1998-1:2004. Nonetheless, isolated bridges with T
eff
> 4 s deserve special attention, due to their inherently low stiffness against any horizontal action.
NOTE 2: For a pier of height H with a displacement stiffness K (kN/m), supported by a foundation with
i si
translation stiffness K (kN/m), rotation stiffness K (kNm/rad), and carrying isolator unit i with effective
ti fi
stiffness K (kN/m), the composite stiffness K is (see Figure 7.5N):
bi eff,i
2
1 1 1 H
1
i
= + + + (7.11N)
K
K K K K
eff,i bi si fi
ti
F
i
The flexibility of the isolator and its relative displacement d = typically is much larger than the other
bi
K
bi
components of the superstructure displacement. For this reason the effective damping of the system depends
only on the sum of dissipated energies of the isolators, ΣE , and the relative displacement of the isolator is
Di
practically equal to the displacement of the superstructure at this point (d /d = K /K ≅ 1).
bi id eff,i bi


Key
A – Superstructure
B – Isolator i
C – Pier i
Figure 7.5N: Composite stiffness of pier and isolator i

4) In 7.6.2 Isolating system
Replace (1)P to (5) by:
(1)P The required increased reliability of the isolating system (see 7.3(4)P) shall be
implemented by designing each isolator i for increased design displacements d :
bi,a
5

---------------------- Page: 7 ----------------------
SIST EN 1998-2:2006/kprA1:2008
EN 1998-2:2005/prA1:2008 (E)
d = γ d (7.19)
bi,a IS bi,d
where γ is an amplification factor that is applied only on the design seismic displacement d of
IS bi,d
each isolator i resulting from one of the procedures specified in 7.5.
If the spatial variability of the seismic action is accounted for through the simplified method of
3.3(4), (5), (6) and (7)P, the increased design displacements shall be estimated by application of
the rule of 3.3(7)P, where the displacements d due the inertia response determined in
bi,d
accordance with one of the methods in 7.5 shall be amplified in accordance with expression
(7.19) above, while those corresponding to the spatial variability determined in accordance with
3.3.(5) and (6), need not be amplified.
NOTE The value ascribed to γ for use in a country may be defined in its National Annex. The
IS
γ = 1,50.
recommended value is
IS
(2)P The maximum total displacement of each isolator unit in each direction d shall be
m,i
verified from expression (7.19a) by adding to the above increased design seismic displacement,
the offset displacement d potentially induced by:
G,i
a) the permanent actions;
b) the long-term deformations (post-tensioning, shrinkage and creep for concrete decks) of the
superstructure; and
c) 50% of the thermal action.

d ≥ d + d                                                (7.19a)
m,i G,i bi,a

NOTE An additional condition for the displacement capacity d of the
...