E urocode 3 : Design of Steel Structures “ ready for practice” p ractice”
EUROCODES Background and Applications, Brussels, 19 th Februar February y 200 8 Prof. Ir. Frans Frans Bijlaa Bijlaard rd February 22, 2008 1
Vermelding Faculty of Civil onderdeel Engineering organisatie and Geosciences
Contents of Presentation
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History Histor y and and Con Contex textt of of Euro Eurocod code e3 Stru St ruct ctur ure e of Eur Euroc ocod ode e3 Safety Level Introd Int roduct uction ion of of Euroco Eurocode de 3 in the the Desi Design gn Practice Conclusions
February 22, 2008
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Histor His tory y and Conte Co ntex x t of E uroc uro c ode od e 3 Design of Steel Structures NEN
AFNOR
EN
DIN BS
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Histor His tory y and Conte Co ntex x t of E uroc uro c ode od e 3 Design of Steel Structures •
• • • •
Design in one country followed by erection in another country Standard building rules for whole Euro-market Easier to work in other countries More efficient transfer of research results in rules Harmonized core material for local handbooks, design aids and educational material
February 22, 2008
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Histor His tory y and Conte Co ntex x t of E uroc uro c ode od e 3 Design of Steel Structures “CHALLENGE FOR EUROCODES” • •
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Ensure structurally safe and serviceable structures Provide rules which are sufficiently detailed to avoid disputes Facilitate international competition on an even playing field Permit innovation in accordance with essential principles
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CEN TC250 EUROCODES EC 0 : Basis of design Hor.. group 1: Termin Hor Terminolog ology y Hor.. group Hor group 2: Bridge Bridgess Hor.. grou Hor group p 3: Fire Fire
SC1 EC1 : Actions
SC2 SC3 EC2: EC3: February 22, 2008 Concrete Steel
SC4 EC4: Composite
SC5 EC5: Timber
SC6 EC6: Mason
SC7 EC7: Geo
SC8 EC8: Earthq
SC9 EC9: 6 Alu
RELATION WITH OTHER EN’s EN 1990 1990 EN Basis of of Design Design Basis
EN 1090 1090 EN Execution Execution
EN 1991 1991 EN Actions Actions
EN 1993 1993 EN Steel Structures Structures Steel
EN :: Steels Steels EN EN :: Sections Sections EN EN :: Bolts Bolts EN
EN 1997 1997 Geotech. Geotech. EN EN 1998 1998 Earthquake Earthquake EN
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EN :: Welding Welding EN
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Stru cture of Eurocode E urocode 3 General Gener al P arts •
EN 1993-1-1:
General rules and rules for buildings
Rules for strength and stability Rules specific for Buildings
February 22, 2008
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Stru cture of Eurocode E urocode 3 General Gener al P arts •
EN 1993-1-2: 5
Structural fire design Stages Stages of a natural natural fire fire -- and fire and the the the standard fire test curve Temperature Pre-Flashover
Post-Flashover 1000-1200°C
Flashover
Natural fire curve
ISO834 standard fire curve Time Ignition Igni tion - Smoul Smoulderin dering g
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Heating
Cooling ….
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Stru cture of Eurocode E urocode 3 General Gener al P arts •
prEN 1993-1 1993-1-3: -3:
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Supplementary Supplementar y rules for cold forme formed d members and sheeting
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Stru cture of Eurocode E urocode 3 General Gener al P arts •
prEN 1993-1-4:
•
prEN 1993-1 1993-1-5: -5:
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Supplementary ru rules fo for st stainless steels Plated struct structural ural eleme elements nts (in-pla (in-plane ne loaded)
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Stru cture of Eurocode E urocode 3 General Gener al P arts • •
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prEN 1993-1-6: Strength an and st stability of of sh shells prEN 1993-1- 7: Plated st structural el elements (transversely loaded) EN 1993-1- 8: Design of joints Tensio Tension n zone zone
Shear zone
V Compression zone
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M
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Stru cture of Eurocode E urocode 3 General Gener al P arts • •
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EN 19 1993 93-1 -1-- 9: EN 1993-1-10:
Fatigu Fati gue e Material toughness and throughthickness properties prEN 1993-1 1993-1-11: -11: Desig Design n of struct structures ures with tension elements prEN pr EN 19 1993 93-1 -1-1 -12: 2: Ad Addi diti tion onal al rul rules es for for the the ext exten ensi sion on o of f EN 1993 up to steel grades S700
February 22, 2008
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Stru cture of Eurocode E urocode 3 Application App lication P arts •
prEN 1993-2:
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Steel bridges
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Stru cture of Eurocode E urocode 3 Application App lication P arts •
prEN 1993-3-1:
Towers an and Ma Masts Masts and Towers
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Stru cture of Eurocode E urocode 3 Application App lication P arts • • • •
prEN 19 prEN 1993 93-3 -3-2 -2:: prEN 1993-4-1: prEN pr EN 19 1993 93-4 -4-2 -2:: prEN 1993-4-3:
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Chi C himne mneys ys Silos Tankss Tank Pipelines
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Stru cture of Eurocode E urocode 3 Application App lication P arts • •
prEN 1993-5: prEN 1993-6:
P i l i ng Crane supporting structures
y
y
y
y
z
z
z z
(a)
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(b)
(c)
(d)
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Safety Level
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Safety Level
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In applying the rules in Eurocode 3 a structural safety is reached of not less than the reliability index
β = 3,8 •
Member states are entitled to choose their own safety level for structures
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Safety Level •
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The rules are set up such that they contain safety elements of which the value can be chosen by the individual member state. These safety elements are for instance the partial (safety) factors for the resistance (limit states) of structural elements. For these safety elements in the Eurocodes so-called recommended values are given in notes accompanying the clauses containing these safety elements.
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Safety Level
•To
promote harmonization of design rules throughout Europe the Commission strongly advises to choose the recom rec om m ended values val ues for these safety elements.
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I ntroduction of Eurocode E urocode 3 in the Design Practice •
Criticism: Eurocode 3 is very advanced but it is complex to use
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To help the designer in practice there is a need for: -Background information -Introduction courses with worked examples -User-friendly software (“expert-systems”)
February 22, 2008
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I ntroduction of Eurocode E urocode 3 in the Design Practice •
Criticism: Eurocode 3 is very advanced but it is complex to use
•
Not “si “simpl mple e rules rules sel selll steel steel”” but “Si m ple TOOLS T OOLS sell St eel”
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Conclusions •
The process of harmonization of design standards of the member countries of CEN did take a period of about three decade decades. s. Compare Compared d to the “life “life time” of an existing code in a country of about 15 years, for the Eurocodes this period is not so bad.
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Eurocode Euroco de 3 “De “Desig sign n of Ste Steel el Stru Structu ctures res”” com compri prises ses a fairly complete set of design codes for uniquely designed structures and for a wide range of structural steel products.
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Conclusions •
The introduction of the Eurocodes in the design practice needs great care. Design examples, guide lines, design tools (special software) should be developed in the various countries. Explanations of differences and the justification for these changes should be supplied to support the acceptation of the Eurocodes.
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To support these local activities in the various member states, background documents need to be drafted on which local design tools and examples need be based.
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THAN K YOU FOR YOUR AT ATT TENT ENTII ON
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