Design Guide 34
Steel-Framed
Stairway Design
Steel-Framed Stairway
Design
Adam D. Friedman SE PE
All rights reservedl. This book or any port thereof must not be reproduced in anyform without the written permission of the publisher. The AlSC logo is α registered trademark of AISC.
The information presented in this publication has been prepared following recognized principles of design andconstruction. While it is believed to be accurate this information should not be used or relied upon for any specificapplication without petent professional examination and verification of its accuracy suitability and applicability by a licensed engineer or architect. The publication of this information is not a representation ormembers or of any other person named herein that this information is suitable for any general or particular use or of fredom from infringement of any patent or patents. All representations or warranties express or implied publication assumes all liability arising from such use. other than as stated above are specifically disclaimed. Anyone making use of the information presented in this
pe sapog auo Aq padojaap sauapin pue spepues uodn Buja uaum pasoaxa aq snu uoneincorporated by reference herein since such material may be modified or amended from time to time subsequentto the printing of this edition. The American Institute of Steel Construction bears no responsibility for such material other than to refer to it and incorporate it by reference at the time of the initial publication of this edition.
Printed in the United States of America
Author
Adam D. Friedman S.E. P.E. is an associate at Computerized Structural Design S.C. His background includes the structural design of stairways for a variety of uses with additional experience in industrial design connection design and constructionengineering related to structural steel.
Acknowledgments
this Design Guide and to thank theAmerican Institute ofSteel Construction for funding the preparation of this Guide He The author wishes to acknowledge the support provided by Computerized Structural Design S.C. during the development ofwould also like to thank the following people for assistance in the review of this Design Guide. Their ments andsuggestions have been invaluable.
Victor ShneurMarc SorensonJennifer Traut-Todaro Gary VioletteRon Yeager
Craig ArchackiDavid BoyerJames Fisher Steve HerlacheLutfur KhandakerMichael Kempfert Lawrence Kruth
Joe LawrenceMargaret MatthewCurt Miller Robert NeumannDavis ParsonsDarin Riggleman Casey Peterson
Preface
qs ps so psds and related ponents. Background information regarding stairways code requirements design methods and designexamples are presented. The goal of this Design Guide is to provide sufficient information for a structural engineer to pletethe design of a steel-framed stairway or provide adequate guidance to delgate this work to another engineer or stair designer.
iv
TABLEOFCONTENTS
PURPOSE ... .1
CHAPTER1INTRODUCTION. 3
1.1 OBJECTIVE AND SCOPE .31.2 DESIGN PHILOSOPHY .3
CHAPTER2GENERALINFORMATION......
2.1 STAIR TYPES Straight Stairs. .52.1.1 2.1.2 Circular Stairs. .5 .52.1.4 2.1.3 Alternating Tread Stairs . Curved Stairs . .7 .72.1.5 Ships Ladder . .72.2 2.2.1 STAIR CLASSES Industrial Class. . .8 .72.2.2 2.2.3 Commercial Class. Service Class. -82.2.4 Architectural Class . 8 .92.3 STAIR NOMENCLATURE .9
CHAPTER3 STAIRWAY CODE REQUIREMENTS....
3.1 APPLICABLE CODES. 113.2 STAIRWAY LOAD COMBINATIONS ANDDESIGN LOADS. Load Combinations .11 3.2.1 .113.2.2 Dead Loads . .113.2.4 3.2.3 Environmental Loads. . . . Live Loads. .12 .133.2.5 3.2.6 Seismic Loads Thermal Loads .14 .153.2.7 General Structural Integrity and3.3 SERVICEABILITY REQUIREMENTS Notional Loads. .16 .163.3.1 Seismic Relative Displacements. General Requirements .163.4 STAIRWAY LAYOUT AND 3.3.2 .173.4.1 Stairway Based on Intemational RECOMMENDATIONS .....18Building Code .183.4.2 Stairway Based on Oecupational Safety and Health AdministrationRegulations .183.4.3I Local Requirements and Special Considerations . .183.4.4 Determining Stair Opening Size......2
CHAPTER4 STAIRWAY DESIGN.............27 3.5
4.1 TREAD AND RISER CONSTRUCTION .....274.1.1 Integral Pan Tread and Riser with Concrete4.1.2 Steel Plate . Fil. .27 4.1.34.1.4 Steel Grating Nonsteel Options. .27 .284.2 TREAD AND RISER CONNECTIONS .284.2.1 Direet Welding Carrier Angle or Plate . .28 4.2.2 .284.2.3 Other Connection Options . 284.3 4.3.1 STRINGER CONSTRUCTION. Stringer Member Types .28 .284.3.2 Design Method versus Horizontal Plane Method Methodology-Sloping BeamExamples . .284.3.3 Design MethodologySimple Span Frame Analysis . .33 versus4.4 STRINGER UNBRACED LENGTH. 334.6 4.5 LANDING CONSTRUCTION LANDING SUPPORT. .344.6.1 Integrated Landing . Post-Supported Landing. .34 4.6.2 .344.6.3 Hanger-Supported Landing. 354.6.4 Building Supports . .35
CHAPTER 5 LATERAL BRACING AND DIAPHRAGM DESIGN. .37
5.1 STAIR FLIGHT ASSEMBLY 375.2 LANDING DIAPHRAGMS .375.2.1 Cast-in-Place Deck. Concrete .37 over Metal5.2.2 Cast-in-Place Concrete over Stiffened5.2.3 Plate . Checkered Plate Flooring .37 .375.3 HORIZONTAL BRACING. VERTICAL AND .37 5.3.1Tension-Only Bracing. .375.3.2 5.3.3 Tension-Compression Bracing. Moment Frames .37 .37
CHAPTER6STAIRWAY CONNECTIONS......39
6.1 STEEL STAIRWAY FRAMING INTO STEELSUPPORT STRUCTURE.6.1.1 6.1.2 AISC Standard Shear Connections .... Axial and Hanger Connections . . .39 .39
