StructuralDesignActions
Part 5:Earthquakeactions-NewZealand
NZS 1170.5:2004
This New Zealand Standard was prepared by Technical Committe BD-006-04-11 Earthquake Loadings inNew Zealand under Joint Committe BD-006 General Design Requirements and Loading on Structures. Itwas approved by the Council of Standards New Zealand on 21 December 2004. It was published on 22 December 2004.
The following are the members of Technical Committee BD-006-04:
Mr Andrew King (Chair) Prof Des BullMr Charles Clifton Dr David DowrickMr Rob Jury DrGracme McVerryProf Peter MossDr Arthur O'Leary
The following are represented on Committee BD-006:
Association of Consulting Engineers AustraliaAustralian Building Codes Board Australian Institute of Steel ConstructionCement and Concrete Association of Australia Building Research Association of New ZealandCSIRO Building Construction and Engineering Cyclone Testing Station James Cook UniversityElectricity Supply Association of AustraliaHousing Industry Association Institution of Engineers AustraliaInstitution of Professional Engineers New Zealand Master Builders AustraliaNew Zealand Heavy Engineering Research Association Steel Reinforcement Institute of AustraliaUniversity of Canterbury New ZealandUniversity of Melbourne University of Newcastle
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NewZealand StandardTM
Structuraldesignactions
Part5:Earthquakeactions- NewZealand
Previous edition NZS 4203:1992 (Part)
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PREFACE
This Standard was prepared by the Standards New Zealand Technical Committee BD/6/4/11. This was initially a Joint Standards Australia/Standards New Zealand TechnicalSubmittee of Committee BD-006 General Design Requirements and Loading onThe development of a Joint Earthquake Standard proved to be impractical and hence separatecountry spccific Standards were proceeded with as part of the 1170 suite of Standards.Itfollows the philosophy and principles that are set out in the Preface to Part 0.
This Standard taken together with the other joint Parts of the 1170 suite is to supersede NZS 4203:1992 General structural design and design loadings for buildings.However NZS 4203 will remain current in New Zealand for a transition period after publication toallow projects currently under way to be pleted and for the Department of Building and Housing to follow its processes for the citation of the 1170 series of Standards as verificationmethods for the New Zealand Building Code.
The 1170 series Structural design actions prises the following parts each of which has addns e sepagsqnd s eeuuouueduooe ue
AS/NZS 1170 Structural design actions
AS/NZS 1170.0:2002 Part 0: General principles
AS/NZS 1170.1:2002 Part 1: Permanent imposed and other actions
AS/NZS 1170.2:2002 Part 2: Wind actions
AS/NZS 1170.3:2003: Part 3: Snow and ice actions
NZS 1170 Structural design actions
NZS 1170.5:2004 Part 5: Earthquake actions New Zealand
(Also to be published is AS 1170.4 Earthquake actions Australia which will haveapplication only in Australia.)
The Commentary to this Standard is NZS 1170.5 Supplement 1 Structural design actionsCommentary is intended to provide background to the various provisions in the Standard tosuggest approaches that may satisfy the intent of the Standard and if appropriate describe differences between this and previous editions of the Standard. References are provided forfurther reading and these are given at the end of cach section of the Commentary.
application of the Appendix to which they apply. A normative’ Appendix is an integral part of a Standard whereas an *informative’ Appendix is only for information and guidance. TheStandard ineludes Appendix D Requirements for material design Standards’as an informative Appendix that is included to guide developers of material specific structuraldesign Standards that are intended to be used in conjunction with NZS 1170.5. Appendix Ddoes not have application to the design of a specific structure where a conforming material specific structural design Standard is being used.
CONTENTS
SECTION1SCOPE AND GENERAL ...51.1 SCOPE. .51.2DETERMINATION OFEARTHQUAKEACTIONS 1.3 LIMIT STATES. .51.4 SPECIAL STUDIES1.5 REFERENCEDDOCUMENTS... 1.6 UNITS .61.7 DEFINITIONS.. .61.8 NOTATION....SECTION2 VERIFICATION f.2.2 STRUCTURALTYPES 2.1 GENERAL REQUIREMENTS..2.3ULTIMATELIMITSTATEVERIFICATION 2.4SERVICEABILITYLIMITSTATEVERIFICATION .82.5DEFORMATION CONTROL.. .9 92.6 STRUCTUREPARTS. .9SECTION 3 SITE HAZARD SPECTRA. 103.1 ELASTIC SITE SPECTRA FOR HORIZONTAL LOADING 3.2SITE HAZARD SPECTRA FOR VERTICAL LOADING 01 21SECTION 4STRUCTURAL CHARACTERISTICS 4.1 PERIOD OF VIBRATION . 23 234.2SEISMIC WEIGHT AND SEISMIC MASS 234.4STRUCTURALPERFORMANCE FACTOR S 4.3STRUCTURALDUCTILITYFACTOR 24 244.5 STRUCTURAL IRREGULARITY... 24SECTION 5DESIGN EARTHQUAKEACTIONS. 275.2 HORIZONTAL DESIGN ACTION COEFFICIENTS AND DESIGN SPECTRA . 27 5.1 GENERAL... 275.3APPLICATION OFDESIGNACTIONS 295.4VERTICALDESIGN ACTIONS. 305.5GROUND MOTION RECORDSFORTIME HISTORYANALYSES. 5.6 CAPACITY DESIGN. 30 32SECTION 6 STRUCTURALANALYSIS... 346.1GENERAL... 346.2 EQUIVALENT STATIC METHOD. 6.3 MODAL RESPONSE SPECTRUM METHOD. 35 366.4NUMERICAL INTEGRATION TIME HISTORY METHOD. 376.5P.DELTAEFFECTS... 6.6 ROCKING STRUCTURES AND STRUCTURAL ELEMENTS. ..41 39SECTION 7EARTHQUAKEINDUCED DEFLECTIONS. 427.2 DETERMINATION OF DESIGN HORIZONTAL DEFLECTIONS ..427.3DETERMINATION OF DESIGN INTER-STOREY DEFLECTION. 7.4HORIZONTALDEFLECTION LIMITS 437.5 INTER-STOREY DEFLECTION LIMITS.... .44
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