AS 1170.4-1993

1 - AS 1170.4-1993 MINIMUM DESIGN LOADS ON STRUCTURES - EARTHQUAKE LOADS
4 - PREFACE
5 - CONTENTS
7 - FOREWORD
10 - SECTION 1 SCOPE AND GENERAL
10 - 1.1 SCOPE
10 - 1.2 REFERENCED DOCUMENTS
10 - 1.3 DEFINITIONS
10 - 1.3.1 Acceleration coefficient
10 - 1.3.2 Base
11 - 1.3.3 Base shear
11 - 1.3.4 Bearing wall system
11 - 1.3.5 Braced frame
11 - 1.3.6 Building frame system
11 - 1.3.7 Concentric braced frame
11 - 1.3.8 Diaphragm
11 - 1.3.9 Dual system
11 - 1.3.10 Ductility
11 - 1.3.11 Drift
11 - 1.3.12 Earthquake design category
11 - 1.3.13 Earthquake resisting system
11 - 1.3.14 Eccentric braced frame
11 - 1.3.15 Hazardous facility
11 - 1.3.16 Horizontal bracing system
11 - 1.3.17 Intermediate moment resisting frame (IMRF)
11 - 1.3.18 Loadbearing wall
11 - 1.3.19 Moment resisting frame system
11 - 1.3.20 Non-loadbearing wall
11 - 1.3.21 Ordinary moment resisting frame (OMRF)
12 - 1.3.22 Orthogonal effect
12 - 1.3.23 P-delta effect
12 - 1.3.24 Shear wall
12 - 1.3.25 Soft storey
12 - 1.3.26 Space frame
12 - 1.3.27 Special moment resisting frame (SMRF)
12 - 1.3.28 Static eccentricity
12 - 1.3.29 Storey
12 - 1.3.30 Storey drift
12 - 1.3.31 Storey drift ratio
12 - 1.3.32 Storey height
12 - 1.3.33 Storey shear
12 - 1.3.34 Storey strength
12 - 1.3.35 Structure
12 - 1.3.36 Structural base
12 - 1.3.37 Structure classification
12 - 1.3.38 Vertical load-carrying frame
12 - 1.3.39 Weak storey
12 - 1.4 NOTATION
14 - 1.5 METHODS OF DETERMINATION OF EARTHQUAKE LOADS
14 - 1.6 EARTHQUAKE LOAD COMBINATIONS
14 - 1.6.1 Limit states design
14 - 1.6.2 Permissible stress design
15 - SECTION 2 GENERAL REQUIREMENTS
15 - 2.1 GENERAL
15 - 2.2 STRUCTURE CLASSIFICATION
15 - 2.2.1 General
15 - 2.2.2 Domestic structures
15 - 2.2.3 General structures
15 - 2.3 ACCELERATION COEFFICIENT
25 - 2.4 SITE FACTOR
26 - 2.5 IMPORTANCE FACTOR
26 - 2.6 EARTHQUAKE DESIGN CATEGORY
26 - 2.7 REQUIREMENTS FOR GENERAL STRUCTURES
26 - 2.7.1 General
27 - 2.7.2 General structures of earthquake Design Category
27 - 2.7.3 General structures of earthquake Design Category B
27 - 2.7.4 General structures of earthquake Design Category C
27 - 2.7.5 General structures of earthquake Design Category D
28 - 2.7.6 General structures of earthquake Design Category E
28 - 2.8 STRUCTURAL SYSTEMS OF BUILDINGS
29 - 2.9 CONFIGURATION
29 - 2.9.1 General
29 - 2.9.2 Plan configuration
29 - 2.9.3 Vertical configuration
30 - 2.10 DEFLECTION AND DRIFT LIMITS
30 - 2.10.1 Portion of structures
30 - 2.10.2 Adjacent structures
31 - SECTION 3 DOMESTIC STRUCTURES
31 - 3.1 GENERAL
31 - 3.2 REQUIREMENTS FOR EARTHQUAKE DESIGN CATEGORIES
31 - 3.2.1 Earthquake Design Category H1
31 - 3.2.2 Earthquake Design Category H2
31 - 3.2.3 Earthquake Design Category H3
31 - 3.3 STRUCTURAL DETAILING REQUIREMENTS FOR DOMESTIC STRUCTURES
31 - 3.3.1 General
31 - 3.3.2 Wall anchorage
31 - 3.4 STATIC ANALYSIS FOR NON-DUCTILE DOMESTIC STRUCTURES OF EARTHQUAKE DESIGN CATEGORY H3
31 - 3.4.1 Horizontal forces
31 - 3.4.2 Earthquake base shear
32 - 3.4.3 Vertical distribution of horizontal earthquake forces
32 - 3.4.4 Torsional effects
32 - 3.5 NON-STRUCTURAL COMPONENTS
33 - SECTION 4 STRUCTURAL DETAILING REQUIREMENTS FOR GENERAL STRUCTURES
33 - 4.1 GENERAL
33 - 4.2 STRUCTURAL DETAILING REQUIREMENTS FOR STRUCTURES OF EARTHQUAKE DESIGN CATEGORY A
33 - 4.2.1 Ductile structures
33 - 4.2.2 Non-ductile structures
33 - 4.3 STRUCTURAL DETAILING REQUIREMENTS FOR STRUCTURES OF EARTHQUAKE DESIGN CATEGORY B
33 - 4.3.1 General
33 - 4.3.2 Load paths, ties and continuity
33 - 4.3.3 Wall anchorage
33 - 4.4 STRUCTURAL DETAILING REQUIREMENTS FOR STRUCTURES OF EARTHQUAKE DESIGN CATEGORIES C, D AND E
33 - 4.4.1 General
34 - 4.4.2 Ties and continuity
34 - 4.4.3 Diaphragms
34 - 4.4.4 Bearing walls
34 - 4.4.5 Openings
34 - 4.4.6 Footing ties
35 - SECTION 5 REQUIREMENTS FOR NON-STRUCTURA L COMPONENTS
35 - 5.1 GENERAL REQUIREMENTS
35 - 5.1.1 General
35 - 5.1.2 Forces on components
35 - 5.1.3 Interrelationship of components
35 - 5.1.4 Connections and attachments
35 - 5.1.5 Earthquake coefficients
37 - 5.2 REQUIREMENTS FOR ARCHITECTURAL COMPONENTS
37 - 5.2.1 Forces
38 - 5.2.2 Exterior wall panel attachment
38 - 5.2.3 Component deformation
38 - 5.2.4 Out-of-plane bending
38 - 5.3 REQUIREMENTS FOR MECHANICAL AND ELECTRICAL COMPONENTS
38 - 5.3.1 Forces
38 - 5.3.2 Ducts and piping distribution systems
39 - 5.4 AMPLIFICATION FACTOR
39 - 5.4.1 Attachment amplification factor
39 - 5.4.2 Height amplification factor
40 - SECTION 6 STATIC ANALYSIS
40 - 6.1 GENERAL
40 - 6.2 HORIZONTAL FORCES
40 - 6.2.1 General
40 - 6.2.2 Earthquake base shear
40 - 6.2.3 Earthquake design coefficient
40 - 6.2.4 Structure period
41 - 6.2.5 Gravity load
41 - 6.2.6 Structural response factor
41 - 6.3 VERTICAL DISTRIBUTION OF HORIZONTAL EARTHQUAKE FORCES
44 - 6.4 HORIZONTAL SHEAR DISTRIBUTION
44 - 6.5 TORSIONAL EFFECTS
44 - 6.5.1 Introduction
44 - 6.5.2 Static eccentricity
44 - 6.5.3 Design eccentricities
46 - 6.5.4 Horizontal torsional moments
46 - 6.5.5 Design action effects resulting from torsional moments
46 - 6.6 STABILITY EFFECTS
46 - 6.7 DRIFT DETERMINATION AND P-DELTA EFFECTS
46 - 6.7.1 General
46 - 6.7.2 Storey drift determination
47 - 6.7.3 P-delta effects
47 - 6.8 VERTICAL COMPONENT OF GROUND MOTION
48 - SECTION 7 DYNAMIC ANALYSIS
48 - 7.1 GENERAL
48 - 7.2 EARTHQUAKE ACTIONS
49 - 7.3 MATHEMATICAL MODEL
49 - 7.4 ANALYSIS PROCEDURES
49 - 7.4.1 General
49 - 7.4.2 Response spectrum analysis
49 - 7.4.2.1 General
49 - 7.4.2.2 Number of modes
49 - 7.4.2.3 Combining modes
49 - 7.4.2.4 Scaling of results
49 - 7.4.2.5 Directional effects
49 - 7.4.2.6 Torsion
50 - 7.4.3 Time history analysis
50 - 7.5 STABILITY EFFECTS
50 - 7.6 DRIFT DETERMINATION AND P-DELTA EFFECTS
51 - SECTION 8 STRUCTURAL ALTERATIONS
52 - APPENDIX A - STRUCTURE CLASSIFICATION
52 - A1 STRUCTURE CLASSIFICATION
53 - A2 CONFIGURATION
53 - A2.1 General
53 - A2.2 Plan configuration
54 - A2.3 Vertical configuration
57 - APPENDIX B - STRUCTURAL SYSTEM
57 - B1 DUCTILITY
57 - B2 STRUCTURAL SYSTEMS
58 - APPENDIX C - DOMESTIC STRUCTURES
58 - C1 GENERAL
58 - C2 TYPE OF STRUCTURES
58 - C2.1 Ductile structures
58 - C2.2 Non-ductile structures
58 - C3 DETAILING GUIDES
58 - C3.1 Foundation and subfloor framing
59 - C3.2 Wall framing
59 - C3.3 Roof bracing
59 - C3.4 Tiled roofs
59 - C3.5 Gable ends and parapets
60 - APPENDIX D - TYPES OF DYNAMIC ANALYSIS
60 - D1 EARTHQUAKE ACTIONS
60 - D2 RESPONSE SPECTRUM ANALYSIS
60 - D2.1 General
60 - D2.2 Number of modes
61 - D2.3 Combining modes
61 - D3 TIME HISTORY ANALYSIS
62 - APPENDIX E - STRUCTURAL ALTERATIONS
62 - E1 INTRODUCTION
62 - E2 DESIGN
63 - E3 ARCHITECTURAL, MECHANICAL AND ELECTRICAL COMPONENTS

Sets out data and procedures for determining minimum earthquake loads on structures and their components, and also minimum detailing requirements for structures. It does not consider related phenomena such as settlement, slides, subsidence, liquefaction or faulting in the immediate vicinity of a structure. It does not include nuclear reactors, dams, transmission towers, bridges, piers and wharves, which may require special consideration. The Standard is in limit states format. New earthquake maps are defined in terms of an acceleration coefficient instead of the zoning system used in the previous Standard AS 2121. Domestic structures are now included.

This Standard sets out data and procedures for determining minimum earthquake loads on structures and their components. It also sets out minimum detailing requirements for structures. It does not consider related phenomena such as settlement, slides, subsidence, liquefaction or faulting in the immediate vicinity of a structure.This Standard is intended to apply to structures, particularly buildings, non-building structures, fixings and non-structural components including building services and architectural elements.Special structures including nuclear reactors, dams, transmission towers, bridges, piers and wharves may require special considerations, and are not covered by this Standard.NOTE: The date of application of this Standard on a mandatory basis is a matter for the relevant regulatory authorities. With the publication of this Standard, AS 2121 - 1979 becomes an available superseded Standard and will be withdrawn following substantial regulatory implementation of this edition, or within two years of publication of this edition, whichever is the earlier.

First published as part of AS 2121-1979.Revised and redesignated in part as AS 1170.4-1993. First published as part of AS 2121-1979. Revised and redesignated in part as AS 1170.4-1993.