NZS1170.5 2004 Structural Design Actions - Earthquake Actions NZ Supplement

SECTION C8 REQUIREMENTS FOR PARTS AND COMPONENTS ....................................................71

C8.1 GENERAL ....................................................................................................................71

C8.2 DESIGN RESPONSE SPECTRUM FOR PARTS..............................................................72

C8.3 FLOOR HEIGHT COEFFICIENT, C_ti ............................................................................73

C8.4 PART SPECTRAL SHAPE FACTOR ............................................................................74

C8.5 DESIGN ACTIONS ON PARTS ...................................................................................74

C8.6 PART RESPONSE FACTOR, C_ph...............................................................................74

C8.7 CONNECTIONS .........................................................................................................77

C8.8 SPECIAL STUDIES....................................................................................................78

APPENDIX CA COMMENTARY ON APPENDIX A - DEFINITIONS ................................................79

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NZS 1170.5 Supp 1:2004

This New Zealand Standard was prepared by Technical Committee BD-006-04-11, Earthquake Loadings in New Zealand under Joint Committee BD-006, General Design Requirements and Loading on Structures. It was approved by the Council of Standards New Zealand on 21 December 2004. It was published on 22 December 2004.

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The following are the members of Technical Committee BD-006-04:

Mr Andrew King (Chair)

Prof. Des Bull

Mr Charles Clifton

Dr David Dowrick

Mr Rob Jury

Dr Graeme McVerry

Prof. Peter Moss

Dr Arthur O'Leary

The following are represented on Committee BD-006:

Association of Consulting Engineers Australia

Australian Building Codes Board

Australian Institute of Steel Construction

Building Research Association of New Zealand

Cement and Concrete Association of Australia

CSIRO, Building, Construction and Engineering

Cyclone Testing Station – James Cook University

Electricity Supply Association of Australia

Housing Industry Association

Institution of Engineers Australia

Institution of Professional Engineers New Zealand

Master Builders Australia

New Zealand Heavy Engineering Research Association

Steel Reinforcement Institute of Australia

University of Canterbury New Zealand

University of Melbourne

University of Newcastle

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Detailed information about New Zealand Standards can be found by visiting the Standards New Zealand web site at www.standards.co.nz and looking up the relevant Standard in the on-line catalogue.

Alternatively, Standards New Zealand publish an annual printed Catalogue with full details of all current Standards. For more frequent listings or notification of revisions, amendments and withdrawals, Standards New Zealand offer a number of update options. For information about these services, please contact Standards New Zealand.

We also welcome suggestions for improvement in our Standards, and especially encourage readers to notify us immediately of any apparent inaccuracies or ambiguities. Please address your comments to the Chief Executive of Standards New Zealand at the address shown on the back cover.

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This Standard was issued in draft form for comment as DR 00903.

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NZS 1170.5 Supplement 1:2004

Structural design actions

Part 5: Earthquake actions – New Zealand – Commentary

(Supplement to NZS 1170.5:2004)

Previous edition NZS 4203:1992 (Part)

COPYRIGHT

©Standards New Zealand

All rights are reserved. No part of this work may be reproduced or copied in any form or by any means, electronic or mechanical, including photocopying, without the written permission of the publisher.

Published by Standards New Zealand, Private Bag 2439, Wellington 6020.

ISBN 1-86975-019-5

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PREFACE

This Commentary is intended to be read in conjunction with NZS 1170.5:2004 referred to here as the "Standard." It is intended to provide background to the various provisions in the Standard, to suggest 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 for further reading and these are given at the end of each section of the Commentary.

Commentary Clauses are not mandatory.

Clause numbering of the Commentary is identical to that of the Standard except that Clauses are prefixed with the letter 'C'. A cross-reference such as 5.4.1.2 refers to that Clause in the Standard, while C5.4.1.2 refers to the corresponding commentary Clause. Commentary is not provided to all Clauses in the Standard. Some commentary Clauses do not have a corresponding Clause in the Standard.

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CONTENTS

	Page
SECTION C1 SCOPE AND GENERAL	5
C1.1 SCOPE	5
C1.2 DETERMINATION OF EARTHQUAKE ACTIONS	5
C1.3 LIMIT STATES	5
C1.4 SPECIAL STUDIES	6
C1.5 REFERENCED DOCUMENTS	6
SECTION C2 VERIFICATION	7
C2.1 GENERAL REQUIREMENTS	7
C2.2 STRUCTURAL TYPES	11
C2.3 ULTIMATE LIMIT STATE VERIFICATION	12
C2.4 SERVICEABILITY LIMIT STATE VERIFICATION	13
C2.5 DEFORMATION CONTROL	15
C2.6 STRUCTURE PARTS	15
C2.7 PRIMARY AND SECONDARY SEISMIC MEMBERS	15
SECTION C3 SITE HAZARD SPECTRA	17
C3.1 ELASTIC SITE SPECTRA FOR HORIZONTAL LOADING	17
C3.2 SITE HAZARD SPECTRA FOR VERTICAL LOADING	28
SECTION C4 STRUCTURAL CHARACTERISTICS	31
C4.1 PERIOD OF VIBRATION	31
C4.2 SEISMIC WEIGHT AND SEISMIC MASS	32
C4.3 STRUCTURAL DUCTILITY FACTOR	32
C4.4 STRUCTURAL PERFORMANCE FACTOR, Sp	35
C4.5 STRUCTURAL IRREGULARITY	37
SECTION C5 DESIGN EARTHQUAKE ACTIONS	42
C5.1 GENERAL	42
C5.2 HORIZONTAL DESIGN ACTION COEFFICIENTS AND DESIGN SPECTRA	42
C5.3 APPLICATION OF DESIGN ACTIONS	45
C5.4 VERTICAL DESIGN ACTIONS	45
C5.5 GROUND MOTION RECORDS FOR TIME HISTORY ANALYSES	45
C5.6 CAPACITY DESIGN	47
SECTION C6 STRUCTURAL ANALYSIS	50
C6.1 GENERAL	50
C6.2 EQUIVALENT STATIC METHOD	52
C6.3 MODAL RESPONSE SPECTRUM METHOD	52
C6.4 NUMERICAL INTEGRATION TIME HISTORY METHOD	56
C6.5 P-DELTA EFFECTS	60
C6.6 ROCKING STRUCTURES AND STRUCTURAL ELEMENTS	63
SECTION C7 EARTHQUAKE INDUCED DEFLECTIONS	66
C7.1 GENERAL	66
C7.2 DETERMINATION OF DESIGN HORIZONTAL DEFLECTIONS	66
C7.3 DETERMINATION OF DESIGN INTER-STOREY DEFLECTION	67
C7.4 HORIZONTAL DEFLECTION LIMITS	68
C7.5 INTER-STOREY DEFLECTION LIMITS	68

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SECTION C8 REQUIREMENTS FOR PARTS AND COMPONENTS ....................................................71

C8.1 GENERAL ....................................................................................................................71

C8.2 DESIGN RESPONSE SPECTRUM FOR PARTS..............................................................72

C8.3 FLOOR HEIGHT COEFFICIENT, C_ti ............................................................................73

C8.4 PART SPECTRAL SHAPE FACTOR ............................................................................74

C8.5 DESIGN ACTIONS ON PARTS ...................................................................................74

C8.6 PART RESPONSE FACTOR, C_ph...............................................................................74

C8.7 CONNECTIONS .........................................................................................................77

C8.8 SPECIAL STUDIES....................................................................................................78

APPENDIX CA COMMENTARY ON APPENDIX A - DEFINITIONS ................................................79

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