ANSI/ASCE 7-88
ANSI Approved
November 27, 1990
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American Society of Civil Engineers
Minimum Design Loads for
Buildings and Other Structures
Revision and redesignation of
ANSI A58.1-1982
Approved December 1988
American Society of Civil Engineers
Published July 1990
Note: A major revision of this standard dealing
primarily with the seismic provisions is being
balloted by the Committee in 1990 and publication is anticipated for 1991.
Published by the American Society of Civil Engineers
345 East 47th Street
New York, New York 10017-2398
Minimum Design Loads for Buildings and Other Structures
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ABSTRACT
ASCE Standard Minimum Design Loads for Buildings and Other
Structures, (formerly ANSI A58.1) gives requirements for dead,
live, soil, wind, snow, rain and earthquake loads, and their combinations, that are suitable for inclusion in building codes and
other design documents. The basis of the requirement is described in the Commentary. The structural load requirements
provided by this standard are intended for use by architects,
structural engineers, and those engaged in preparing and
administering local building codes.
Library of Congress Cataloging-in-Publication Data
Minimum design loads for buildings and other structures/
American Society of Civil Engineers.
p. cm.
"ASCE 7-88 formerly ANSI A58.1, revision of ANSI
A58.1-1982."
"Published July 1990:'
"Approved December 1988."
ISBN 0-87262-742-X
1. Structural engineering. 2. Building-Standards-United
States. I. American Society of Civil Engineers.
TH851.M56 1990
624.1 '72'021873-dc20
90-1065
CIP
Authorization to photocopy material for internal or personal use
under circumstances not falling within the fair use provisions of
the Copyright Act is granted by ASCE to libraries and other users
registered with the Copyright Clearance Center (CCC) Transactional Reporting Service, provided that the base fee of $1.00
per article plus $.15 per page is paid directly to CCC, 27 Congress Street, Salem, MA 01970. The identification for ASCE
Bboks is 0-87262188. $1 + .15. Requests for special permission or bulk copying should be addressed to Reprints/Permis·
sions Department.
Copyright © 1990 by the American Society of CMI Engineers,
All Rights Reserved.
Library of Congress Catalog Card No: 90-1065
ISBN 0·87262-742-X
Manufactured in the United States of America.
Minimum Design Loads for Buildings and Other Structures
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STANDARDS
In April 1980, the Board of Direction approved
ASCE Rules for Standards Committees to govern the
writing and maintenance of standards developed by
the Society. All such standards are developed by a
consensus standards process managed by the Technical Council on Codes and Standards. The consensus
process includes balloting by the balanced standards
committee made up of Society members and nonmembers, balloting by the membership of ASCE as a
whole and balloting by the public. All standards are
updated or reaffirmed by the same process at intervals
not exceeding 5 years.
ANSI/ ASCE 1-82 N- 725 Guideline for Design
and Analysis of Nuclear Safety Related Earth
Structures
ANSI/ ASCE 2-84 Measurement of Oxygen
Transfer in Clean Water
ANSI/ ASCE 3-84 Specifications for the Design
and Construction of Composite Slabs and
Commentary on Specifications for the Design
and Construction of Composite Slabs
ASCE 4-86 Seismic Analysis of Safety-Related
Nuclear Structures
Building Code Requirements for Masonry
Structures (ACI530-88/ASCE5-88) and
Specifications for Masonry Structures
(ACl530.1-88/ ASCE6-88)
Specifications for Masonry Structures
(ACI530.1-88/ ASCE6-88)
ASCE 7-88 Minimum Design Loads for
Buildings and Other Structures
iii
Minimum Design Loads for Buildings and Other Structures
Minimum Design Loads for Buildings and Other Structures
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FOREWORD
the American Society of Civil Engineers, or of any
other person named herein, that this information is
suitable for any general or particular use or promises
freedom from infringement of any patent or patents.
Anyone making use of this information assumes all
liability from such use.
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The material presented in this publication has been
prepared in accordance with recognized engineering
principles. This Standard and Commentary should not
be used without first securing competent advice with
respect to their suitability for any given application.
The publication of the material contained herein is not
intended as a representation or warranty on the part of
v
Minimum Design Loads for Buildings and Other Structures
Minimum Design Loads for Buildings and Other Structures
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ACKNOWLEDGEMENTS
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The American Society of Civil Engineers (ASCE)
acknowledges the devoted efforts of the Minimum
Design Loads for Building and Other Structures
Standards Committee of the Technical Council on
Codes and Standards. This group comprises individuals from many backgrounds including: consulting
engineering, research, construction industry, education, government, design, and private practice.
The previous work of the A58 Committee of the
Robert G. Albrecht
Demirtas C. Bayer
John E. Breen
Roderick B. Buchan
Vincent R. Bush
Kevin D. Callahan
William L. Casper
Jack Edward Cermak
Charles W. Chambliss
Edward Cohen, Chairman (1968-1988)
C Allin Cornell
Ross Barry Corotis
Stanley W. Crawley
Charles A. De Angelis
Robert Dillon
D. J. Donaldson
Frank M. Drake
Bruce R. Ellingwood
Lawrence Fischer
John W. Foss
Raymond R. Fox
Theodore Galambos
Satyendra K. Ghosh
Lorenzo Gonzalez
Mircea D. Grigoriu
Gilliam S. Harris
James Robert Harris
Arthur L. Held
Roong-Roj Hemakom
Vincent J. Hession
American National Standards Institute is greatly
acknowledged.
This Standard was prepared through the consensus
standards process by balloting in compliance with
procedures of ASCE's Technical Council on Codes
and Standards. Those individuals who serve on the
Minimum Design Loads for Buildings and Other
Structures Standards Committee are:
Mark B. Hogan
Joseph Horowitz
David A. Hunter, Jr
Albert L. Johnson
Aristides H. Karabinis
Henry V. Kominek
Uno Kula
James G. Mac Gregor
Richard D. Marshall
Rusk Masih
George M. Matsumura
Murvan M. Maxwell
William Mc Guire
Richard McConnell
Robert McCluer
Daniel M. McGee
Kishor C. Mehta
Arthur Monsey
Walter Moore, Jr
Bruce C. Olsen
Robert A. Parsons
Dale C. Perry
Clarkson Wilfred Pinkham
Michael R. Rourke
Basile G. Rabbat
Robert Ratay
Mayasandra K. Ravindra
Lawrence D. Reaveley
Robert K. Redfield
Leslie E. Robertson
William D. Rome
Ronald Sack
Herbert S. Saffir
Edward Salsbury
Michael Sbaglia
John H. Showalter, Jr
Emil Simiu
Howard Simpson
Theodore Stathopoulos
Louis T. Steyaert
Frank W. Stockwell
Donald R. Strand
William J. Tangye
Harry B. Thomas
Wayne N. Tobiasson
Joseph V. Tyrrell
Joseph W. Vellozzi
Donald J. Vild
Richard Alan Vognild
Vincent Wanzek
Marius B. Wechsler
Paul Weidlinger
Yi Kwei Wen
A. Rhett Whitlock
Robert V. Whitman
Lyle L. Wilson
Joseph A. Wintz, III
Alan H. Yorkdale
Edwin G. Zacher
vii
Minimum Design Loads for Buildings and Other Structures
Minimum Design Loads for Buildings and Other Structures
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Contents
PAGE
1. General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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1.1
1.2
1.3
1.4
1.5
1.6
1
Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Basic Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
General Structural Integrity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Classification of Buildings and Other Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Additions to Existing Structures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Load Tests............................................................ 1
2. Combinations of Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.1 Definitions and Limitation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.2 Symbols and Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.3 Combining Loads Using Allowable Stress Design...........................
2.4 Combining Loads Using Strength Design . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2.5 Counteracting Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
1
3
3
3
3
3. Dead Loads................................................................
3.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Weights of Materials and Constructions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.3 Weight of Fixed Service Equipment.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.4 Special Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
5
5
4. Live Loads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 Uniformly Distributed Loads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 Concentrated Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4 Loads on Handrails and Guardrail Systems. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5 Loads Not Specified . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6 Partial Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4. 7 Impact Loads. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.8 Reduction in Live Loads . . . . . . . . . . . . . . . . . . . . .. .. . . . . . . . . . . . . . . . . . . . . . . . .
4.9 Posting of Live Loads . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.10 Restrictions on Loading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.11 Minimum Roof Live Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5
5
5
5
5
5
5
6
6
6
6
7
7
7
5. Soil and Hydrostatic Pressure................................................. 7
5.1 Pressure on Basement Walls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
5.2 Uplift on Floors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
6. Wind Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
6.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
6.2 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.3 Symbols and Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
6.4 Calculation of Wind Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
6.5 Velocity Pressure. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
6.6 Gust Response Factors .................................................. 14
6.7 Pressure and Force Coefficients .......................................... 14
7. Snow Loads ................................................................ 23
7.1 Symbols and Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
7 .2 Ground Snow Loads, p8 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 23
7.3 Flat-Roof Snow Loads, Pr ............................................... 23
7.4 Sloped-Roof Snow Loads, Ps •••......••....••....•..••••...•.•..•....••.. 23
7.5 Unloaded Portions ..................................................... 28
7.6 Unbalanced Roof Snow Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . 28
7.7 Drifts on Lower Roofs (Aerodynamic Shade) ............................... 29
7.8 Roof Projections ....................................................... 29
ix
Minimum Design Loads for Buildings and Other Structures
PAGE
7.9 Sliding Snow . . . . . . • . . . . . . . . . . . • . . . . . . . • • . . • . • . . . . . . . . . . . . . . . . . . . . . • . . • 31
7.10 Extra Loads from Rain-on-Snow ..........•.•............•.........•....• 32
7.11 Ponding Loads ............................•..••....•...•.........•.••.. 32
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8. Rain Loads . • . . . . • . . . . . . . . . • . . . . . . . . . • . . . . • . . • • . • . • • . . . . • . . . • . . . . • • . . . . . . . . 32
8.1 Roof Drainage ................................•..............••.•...... · 32
8.2 Ponding Loads. . . . . . . . . . . . . . . • . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . • . . • . . . . . . 32
8.3 Blocked Drains . . . • . . . . . . . • . . . . . . . . . . . . . . . . • . . • . . . . . . . . . . . . • . . • . • . . . . . . 32
8.4 Controlled Drainage . . . . . . . . . . . . . . . . . . . • . . . . • • . . . . • . . . . . . • . . . . . • . . • . . . . . 32
9. Earthquake Loads. . . . . . . . . . . . . . . . . • . • . . . • . . • . . . . . . . . . . • . . . • . . • . . . . . . . . . • . . . • 32
9.1 General . . . . . . . . . . . . . . . . . • . . . . . • • . . . . • . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . 32
9.2 Definitions .................•...•..........•...•............•....•••..• 32
9.3 Symbols and Notation ...........•.•............•...........••.......•.. 35
9.4 Minimum Earthquake Forces for Structures ...•..........................•. 35
9.5 Distribution of Lateral Forces ............•.••................•.........•• 36
9.6 Overturning . . . • . . . . . . . . . . . . . . . . . . . . . . . • . . . . • . . • . . . • . . • . . . . • . . . • . . • . . • . 38
9.7 Drift and Building Separation ...•........................................ 38
9.8 Alternate Determination and Distribution of Seismic Forces . • . . • . . . . • . . . • . . . . 38
9.9 Structural Systems .•...................••.....................•..•.•.... 39
9.10 Lateral Forces on Elements of Structures and Nonstructural Components. . . . . . • 39
9.11 Connections .•..................•........•...•..•............•........• 40
9.12 Other Requirements ......•................................•..•........• 40
9.13 Essential Facilities .......•.....•.................•..............•.....• 40
10. References • . . . . . . . . . . . . . . . . . . . . . . • . • . . . . . . • . . • . . . • . . • . . . • . . . • . • . • . . . . . • 41
Commentary to American Society of Civil Engineers Standard ASCE 7-88
(Formerly ANSI A58.l) ...•....•...•..•..........•....•....•..•.......•...•..••. 42
l. General ...•.....................•.............•......•..•....•.........••• 42
2. Combinations of Loads . . . . . . . . . . . . . . . . • . . . • . . . . . . . . . . • . . • . . . . . . . . . . • . . . . . • . 46
3. Dead Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . • . . . . . . • . . . . • . . . . . . . . . • . • . . . • . 48
4. Live Loads . . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . • . . . . . . . . . . . • • . . . . . • . . • . 48
5. Soil and Hydrostatic Pressure ••.......•..............•............•..•.....•• 53
6. Wind Loads ..•....•...........•..•........•..•....................•.....•. 55
7. Snow Loads ..•............••.....•...........•........•..•••.•............ 67
8. Rain Loads . . . . . . . . • . . . . . . . . . . . . . . . . • . . • . . . . . . • . . . • . . . . . . . . . . • . . . . . • . . • . . . . 79
9. Earthquake Loads ..........•.....••....................••..............••.. 80
Index ....•..........................•.........•..•............•.....•.....•... 93
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Minimum Design Loads for Buildings and Other Structures
PAGE
List of Tables
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Table 1
Classification of Buildings and Other Structures for Wind, Snow and
Earthquake Loads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Table 2
Minimum Uniformly Distributed Live Loads, L0 • • • • • • • • • • • • • • • • • • • • • • • • 4
Table 3
Minimum Concentrated Loads....................................... 5
Table 4
Design Wind Pressures, p, and Forces, F . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
Importance Factor, I (Wind Loads) ................................... 11
Table 5
Table 6
Velocity Pressure Exposure Coefficient, Kz .••.•...•....•..•.....•...•• 12
Table 7
Basic Wind Speed, V . . . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
Table 8
Gust Response Factors, Gh and Gz •................................... 15
Table 9
Internal Pressure Coefficients of Buidings, GCpi .•.•.••.••.•••.•..••.••. 20
Table 10 External Pressure Coefficients for Arched Roofs, Cp ..•....••....•..•.•. 20
Table 11
Force Coefficients for Monoslope Roofs over Unenclosed Buildings and
Other Structures, Cr . . • • . • . . • • . . . • . . • . . • • . • . . . . . • . . . . • . . . . . . . • . . . . • . 21
Table 12 Force Coefficients for Chimneys, Tanks, and Similar Structures, Cr .•...•. 21
Table 13 Force Coefficients for Solid Signs, Cr .............•.••..•..•...••..... 22
Table 14 Force Coefficients for Open Signs and Lattice Frameworks, Cr •...•...... 22
Table 15 Force Coefficients for Trussed Towers, Cr .•.•.....•..•..............•. 22
Table 16 Force Coefficients for Tower Guys, Co and CL ....•.•..........•...... 22
Table 17 Ground Snow Loads, p8 , for Alaskan Locations . . . . . . . . . . . . . . . . . . . . . . . . 27
Table 18 Exposure Factor,
27
Table 19 Thermal Factor, C1 • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • • 27
Table 20 Importance Factor, !(Snow Loads) ................................... 27
Table 21
Seismic Zone Coefficient, Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Table 22 Occupancy Importance Factor, I (Earthquake Loads) ................... 37
Table 23
Horizontal Force Factor, K, for Buildings and Other Structures ........... 37
Table 24 Soil Profile Coefficient, S . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Table 25 Horizontal Force Factor, Cp, for Elements of Structures and
Nonstructural Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Table C 1 Minimum Design Dead Loads ....................................... 49
Table C2 Minumim Densities for Design Loads from Materials ................... 50
Table C3 Minimum Uniformly Distributed Live Loads ........................... 51
Table C4 Typical Live Load Statistics ......................................... 52
Table C5 Ambient Air Density Values for Various Altitudes ...................... 56
Table C6 Exposure Category Constants ....................................... 56
Table C7 Wind-Speed Data for Locations in the United States .................... 57
Table C8 Probability of Exceeding Design Wind Speed during Reference Period ..... 60
Table C9 Parameters s and 'Y •••••••••••••.•••••.••••..•••••••••••••••••••••• 64
Table ClO Ground Snow Loads at 184 National Weather Service Locations at Which
Load Measurements are Made . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
Table Cl 1 Comparison of Some Site-Specific Values and Zoned Values in
Shaded Areas of Figs. 5, 6, and 7 .................................... 71
Table C12 Factors for Converting from Other Annual Probabilities of Being Exceeded,
and Other Mean Recurrence Intervals, to that Used in this Standard ....... 71
c•................................................
xi
Minimum Design Loads for Buildings and Other Structures
PAGE
List of Figures
Basic Wind Speed . . . . . . • . . . . . • . . • . . . . . . . • . . . . . • . . . • . . . . . . . . . . . . . . . . . 13
External Pressure Coefficients, Cp, for Average Loads on Main Wind-Force
Resisting Systems . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
External
Pressure Coefficients, GCP> for Loads on Building Components and
Fig. 3.
Cladding for Building with Mean Roof Height h
Less than or Equal to 60 Feet. • . .. . . . . . . . . . . . . • . . . . . . . . . . . . . . . . . . . . . . . 17
External Pressure Coefficients, GC P• for Loads on Building Components and
Fig. 4.
Cladding for Building with Mean Roof Height h Greater than 60 Feet . . . . . . 19
Ground Snow Loads, p8, for the Western United States ..•................ 24
Fig. 5.
Ground Snow Loads, p 8, for the Central United States .................... 25
Fig. 6.
Ground Snow Loads, p 8, for the Eastern United States ........•........... 26
Fig. 7.
Graphs for Determining Roof Slope Factor, C5, for Warm and
Fig. 8.
Cold Roofs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Fig. 9.
Balanced and Unbalanced Snow Loads for Hip and Gable Roofs . . . . . . . . . . . 29
Fig. 10. Unbalanced Loading Conditions for Curved Roofs •.........•............ 30
Fig. 11. Balanced and Unbalanced Loads for a Sawtooth Roof .......•...........• 30
Fig. 12. Configuration of Drift on Lower Roofs ....•............................ 31
Fig. 13. Graphs and Equation for Determining Drift Height, h.i . • . . . . . . . . . . . . . . . . . . 31
Fig. 14. Map for Seismic Zones-Contiguous 48 States . . . . . . . . . • . . . . . . . . . . . . . . . . 33
Fig. 15. Map for Seismic Zones-Hawaii, Alaska, and Puerto Rico .........•...... 34
Fig. Cl. Use of Spine Walls ...................•.............................. 45
Fig. C2. Load-Bearing..Intemal Partitions and Change of Slab Span Direction .•..... 45
Fig. C3. Beam Action of Walls . . . . . . . . . . . . . . . . . • . . . . . . . . • . . . . . . . . . . . . . . . . . . . . 45
Fig. C4. Typical Influence Areas . . . . . . . . . . . . . • . . • . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
Fig. CS. Ratio of Probable Maximum Speed Averaged over t Seconds to
Hourly Mean Speed . . . . . . . . . . . . . . . . • . . . . . . . . . . . . . • . . . . . . . . • . . . . . . . . . 61
Fig. C6. Pressure Profile Factor, J, as a Function of 'Y. • • • • • • • • • • • • • • • • • • • • • • • • • • • 62
Fig. C7. Resonance Factor, Y, as a Function of 'Y and the Ratio c/h •.............•. 63
Fig. CS. Structure Size Factor, S ...••..•.•.•••.....••.•••.......•..•.......••• 64
Fig. C9. Design Snow Loads for Example l .................................... 76
Fig. C 10. Design Snow Loads for Example 2 .. .. .. .. . • . . .. .. .. . . .. . . . • .. .. .. .. .. 77
Fig. C 11. Design Snow Loads for Example 3 . . . . . . • • . . . . . • . . . . . . . . . . . . . . • . . . . . . . 78
Fig. C12. Framing that would Require Analysis for Orthogonal Effect
(Zones 3 and 4) •.......•......•....................................• 82
Fig. C13. Steel Frame Buildings ...••.••...................••.....•.....•....... 86
Fig. C14. Reinforced Concrete Frame Buildings .................................. 87
Fig. Cl5. RIC Shear-Wall Buildings ............................................ 88
Fig. C 16. RIC Shear-Wall Buildings with Isolated Shear Walls
Not Interconnected by Frames . . . .. . .. . .. • . .. . .. . . . . . • . . . . . . . . . . . . . . . . 89
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Fig. 1.
Fig. 2.
xii
Minimum Design Loads for Buildings and Other Structures
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Metric Conversion Table
To convert from
To
degree Fahrenheit
foot
ft2
ft3
inch
mile (international)
mile (international
nautical)
mph
pound-force (!bf)
pound
(lb avoirdupois)
lbf/in2 (psi)
lbf/ft
degree Celsius
metre (m)
square metre (m2)
cubic metre (m3)
metre (m)
metre (m)
metre (m)
t°C
km/h
newton (N)
kilogram (kg)
1.609 344*
4.448 222
4.535 924 x 10-1
lbf/ft2
lb/ft2
lb/ft3
Multiply by
=
(t°F - 32)/l.8
3.048 000* x 10-1
9.290 304* 10-2
2.831 685 x 10-2
2.540 000* x 10-2
1.609 344* x 103
1.852 000* x 103
pascal (Pa)
6.894 757 x 103
newton per metre
1.459 390 x 10
(Nim)
4.788 026 x 10
pascal (Pa)
kilogram per square 4.882 428
metre (kg/m2)
kilogram per cubic 1.601 846 x 10
metre (kg/m 3)
*Exact Value
From ASTM E380-89 "Standard for Metric Practice"
xiii
Minimum Design Loads for Buildings and Other Structures