Manual of Steel Construction Load and Resistance Factor Design 3rd Edition

  

Revisions, January 2003

Manual of Steel Construction

Load and Resistance Factor Design

  

3rd Edition

The following technical revisions and corrections have been made

in the second printing of the Third Edition (January, 2003). To facil-

itate the incorporation of revisions and corrections, this booklet

has been constructed using excerpts from revised pages, with cor-

rections noted. The user may find it convenient in some cases to

hand-write corrections; in others, a cut-and-paste approach may be more efficient. vi

Copyright © 2001

by

American Institute of Steel Construction, Inc.

ISBN 1-56424-051-7

  

All rights reserved. This book or any part thereof

must not be reproduced in any form without the

written permission of the publisher.

  

The information presented in this publication has been prepared in accordance

with recognized engineering principles and is for general information only. While

it is believed to be accurate, this information should not be used or relied upon

for any specific application without competent professional examination and

verification of its accuracy, suitability, and applicability by a licensed professional

engineer, designer, or architect. The publication of the material contained herein

is not intended as a representation or warranty on the part of the American

Institute of Steel Construction or of any other person named herein, that this

information is suitable for any general or particular use or of freedom from

infringement of any patent or patents. Anyone making use of this information

assumes all liability arising from such use.

Caution must be exercised when relying upon other specifications and codes

developed by other bodies and incorporated by reference herein since such

material may be modified or amended from time to time subsequent to the

printing of this edition. The Institute 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

First Printing: November 2001

Second Printing: January 2003

  Second Printing: January 2003 with revisions

MERICAN NSTITUTE OF TEEL ONSTRUCTION

A

  

I S C

  b ) are plotted for both W-shapes and channels.

  LRFD Specification for Steel Hollow Structural Sections

  , and Z y .

  , I y

  x , Z x

  1 values for W-shapes and the 0.93 wall-thickness reduction factor for HSS have been considered.

  Code of Standard Practice for Steel Buildings and Bridges

  RCSC Specification for Structural Joints Using ASTM A325 or A490 Bolts

  LRFD Specification for Single-Angle Members

  LRFD Specification for Structural Steel Buildings

  Edition LRFD Manual of Steel Construction is the twelfth major update of the

AISC Manual of Steel Construction, which was first published in 1927. With this revision,

member and connection design information has been condensed back into a single

volume. It has been reorganized and reformatted to provide practical and efficient access

to the information it contains, with a roadmap format to guide the user quickly to the

applicable specifications, codes and standards, as well as the applicable provisions in

those standards. The following specifications, codes and standards are included in or with this Manual:

  This 3 rd

  • 1999

  • 2000

  • 2000
  • 2000
  • 2000
  • AISC Shapes Database V3 CD The following major improvements have been made in this revision:
  • Workable gages for flange fasteners have been reintroduced.
  • The revised T, k and k
  • • Guidance is provided on the new OSHA safety regulations, stability bracing

    requirements and proper material specification.
  • • New information is provided on design drawing information requirements, criteria

    needed for connection design, mill, fabrication and erection tolerances, façade issues, temperature effects and fire protection requirements with summaries of common UL assemblies.
  • Shape information has been updated to the current series.
  • Coverage of round HSS has been added.
  • Dimensions and properties have been added for double channels back-to-back.
  • • Tables of surface and box perimeter, weight/area-to-perimeter ratios and surface

    areas have been expanded to cover all common structural shapes.
  • • A new section on properly specifying materials, including shapes, plates, fasteners

    and other products, has been added.
  • New information on corrosion protection and seismic design has been added.

  • • A new section has been added with design aids for tension members, including

    explicit consideration of net section requirements to ensure connectable member selection.
  • Beam selection tables are included for selection based upon I
  • Beam charts ( φM n vs. L

  • New floor plate deflection and bending design aids have been added.
  • Additional beam diagrams and formulas have been added.
  • A new section has been added with design aids for W-shape beam-columns.

  • New bolt length selection tables have been added.

  I NSTITUTE OF S TEEL C ONSTRUCTION

PREFACE

  vii A MERICAN

  • Bolt entering and tightening clearances have been updated.
  • • Bolting information has been updated for consistency with the 2000 RCSC Specification.

viii

  • • Welding information, including the prequalified welded joint tables, has been

    updated to for consistency with AWS D1.1-2000.
  • • Information on prying action, Whitmore section and strength of coped beams has

    been updated.
  • Selection tables for shear end-plate connections and single-plate connections have been improved and expanded, including single-plate connections with up to 12

  1 rows of bolts and up to 1 / -in. diameter.

  8

  • New information and examples for flexible moment connections has been added as an update of Disque’s historic “type 2 with wind” moment connection design approach.
  • • Previous limitations on the use of moment end-plate connections have been

    relaxed.
  • • Information on the design of anchor rods has been updated, including a new table

    of minimum dimensions for washers used with anchor rods.
  • • Composite member tables have been updated to include coverage of both 4 ksi

    and 5 ksi concrete.
  • • A cross-reference between U.S. customary and Metric shapes series has been

    included.

  In addition, many other improvements have been made throughout this Manual. By the AISC Committee on Manuals and Textbooks, William A. Thornton, Chairman Barry L. Barger, Vice Chairman

  Charles J. Carter Charles R. Page Robert O. Disque Davis G. Parsons II Marshall T. Ferrell David T. Ricker Lanny J. Flynn Marc L. Sorenson Mark V. Holland Scott T. Undershute Bill R. Lindley II Gary C. Violette Leonard R. Middleton Michael A. West William C. Minchin Heath E. Mitchell, Secretary Thomas M. Murray

  

The Committee gratefully acknowledges the following people for their contributions to this

Manual: Abbas Aminmansour, Roger L. Brockenbrough, Jennifer R. Ceccotti, Harry A.

Cole, Richard A. DeVries, Guy J. Engebretson, Areti Gertos, Louis F. Geschwindner, Jr.,

John L. Harris III, Richard C. Kaehler, Suzanne W. Kaehler, Gerald F. Loberger, Jr.,

William T. Segui, Janet S. Tuegel, and Ramulu S. Vinnakota.

  

I S C

  

MERICAN NSTITUTE OF TEEL ONSTRUCTION

A

2 Width,

  1

  7

  1

  1.92

  

8

  /

  

1

  16

  /

  3

  ×8.2 2.39 0.200

  8

  /

  1

  2

  8

  2.03

  

16

  /

  

3

  16

  /

  5

  ×10.5 3.08 0.314

  8

  /

  3

  1

  8

  /

  /

  1

  4

  0.320

  8

  /

  1

  1

  2

  /

  1

  3

  4

  /

  3

  16

  /

  5

  8

  1

  /

  7

  1

  1.89

  

16

  /

  

3

  16

  /

  5

  5.00 5 0.325

  2.64

  8 C5×9

  /

  3

  16

  1.97

  1

  2.19

  

16

  /

  

3

  16

  /

  5

  ×12.25 3.60 0.314

  4

  /

  1

  1

  4

  /

  5

  1

  8

  /

  7

  8

  /

  3

  0.366

  4

  /

  1

  2

  2.30

  

4

  /

  2

  /

  /

  /

  13

  16

  /

  5

  0.343

  8

  /

  1

  2

  2.16

  

4

  /

  

1

  16

  7

  4

  6.00 6 0.437

  3.81

  8 C6×13

  /

  1

  2

  2.09

  

8

  /

  

1

  16

  /

  3

  ×9.8 2.87 0.210

  ×6.7

  5.00 5 0.190

  16

  0.273

  4

  /

  1

  1.47 0.258

  8

  /

  5

  1

  16

  /

  11

  4

  /

  1

  8

  /

  /

  5

  1

  1.60

  

16

  /

  

3

  8

  /

  3

  3.00 3 0.356

  1.76

  8

  /

  

1

  

8

  1

  8

  11/1/02

  Rev. 11/1/02 Rev.

  8

  /

  3

  1

  1.37

  

16

  /

  

1

  8

  /

  1

  1.03 0.132

  /

  1.50

  3

  1

  1.41

  

8

  /

  

1

  16

  /

  3

  1.20 0.170

  2

  /

  1

  1

  5

  1.58

  3

  /

  1.72

  

16

  /

  

3

  16

  /

  5

  4.00 4 0.321

  2.13

  2

  /

  1

  3

  4

  3

  3

  16

  /

  5

  0.320

  4

  /

  3

  1

  1.75

  

8

  /

  

1

  16

  /

  1

  /

  

16

  16

  /

  

1

  8

  /

  1

  1.32 0.125

  8

  /

  5

  1

  1.58

  

8

  /

  

1

  /

  4

  3

  1.58 0.184

  1 ×5.4

  2

  /

  1

  2

  4

  /

  3

  16

  /

  5

  0.296

  

1

  /

  1–30 DIMENSIONS AND PROPERTIES Table 1-5.

  ×25 7.34 0.387

  /

  

3

  16

  /

  5

  3 ×20.7 6.08 0.282

  3.05

  

16

  /

  

3

  8

  /

  3

  4

  2.94

  3 /

  1

  4

  3 /

  9

  8

  1 /

  1

  2

  1 /

  0.501

  8

  1 /

  3

  

16

  3 C10×30

  

4

  

4

  

16

  /

  

3

  8

  /

  3

  ×20 5.87 0.379

  4

  3 /

  1

  8

  7 /

  2

  2.89

  2

1 /

  8.81

  1 /

  ×25 7.34 0.526

  4

  3 /

  1

  8

  1

  16

  7 /

  3.03 3 0.436

  

8

  16

3 /

  11 /

  10.0 10 0.673

  3.17

  2

1 /

  2

  

8

  12

  16

  /

  7

  1

  8

  /

  5

  0.650

  4

  /

  3

  3

  3.72

  /

  /

  

3

  16

  /

  11

  15.0 15 0.716

  14.7

  C15×50

  2 in. in. in. in. in. in. in. in.

  Work- able Gage in.

  Thickness, t f k T

  b f

  Web Flange Distance Thickness, t w

t w

  Depth, d

  C-Shapes (American Standard Channels) Dimensions Shape Area, A

  1

  8

  1 /

  2 ×33.9 9.95 0.400

  12.0 12 0.510

  8.81

  2 C12×30

  8

  /

  3

  3

  3.40

  

16

  /

  

3

  8

  /

  3

  2

  2

  /

  1

  3

  3.52

  

4

  /

  

1

  2

  /

  1

  ×40 11.8 0.520

  4

  /

  1

  2.74

  3

  7

  0.390

  2

  /

  1

  1

  8

  /

  1

  6

  16

  /

  15

  8

  /

  3

  2

  5

  /

  1

  2

  2.53

  

4

  /

  

1

  2

  /

  1

  8.00 8 0.487

  5.51

  8 C8×18.75

  /

  ×13.75 4.04 0.303

  /

  1

  4

  7.00 7 0.419

  4.33

  8 C7×14.75

  /

  3

  1

  4

  /

  1

  2

  2.26

  

8

  /

  

1

  /

  16

  1

  ×11.5 3.37 0.220

  8

  /

  3

  1

  8

  /

  3

  2

  2.34

  

16

  /

  

3

  3

  8

  /

  /

  8

  5 /

  2

  2.65

  

4

  16

1 /

  7 /

  9.00 9 0.448

  5.87

  2 C9×20

  /

  1

  1

  8

  5

  7 /

  2

  2.60

  

8

  /

  

1

  4

  /

  1

  ×15.3 4.48 0.240

  2

  /

  1

  1

  4

  0.413

  16

  /

  2

  3

  2

  2.43

  

8

  /

  

1

  4

  /

  1

  ×13.4 3.94 0.233

  8

  /

  3

  1

  /

  1

  1

  2

  2.49

  

16

  /

  

3

  16

  /

  5

  ×15 4.41 0.285

  2

  1 /

  1

  7

  • – C4×7.25
  • – ×4.5
  • – C3×6
  • – ×5
  • – ×4.1
  • – ×3.5
  • >– † See definition of “Workable Gage” in Nomenclature section at the back of this Man
  • – in Workable Gage column indicates that flange is too narrow to allow tabulation of a workable gage.

  1–36 DIMENSIONS AND PROPERTIES Table 1-7 (cont.).

  2 ×3

  3.63

  3.27

  11.1

  8

  /

  7

  2

  /

  1

  2 ×

  /

  1

  /

  1.05

  1

  1.22 1.77 0.618 L3

  1.27

  1.69 2.75 0.988

  5.75

  4

  /

  1

  1.25 2.19 0.651 ×

  1.27

  1.22

  3.36

  1.48

  1.05 2.66 0.466 ×

  7.12

  8

  16

  /

  5

  1.00 2.06 0.357 ×

  1.07

  1.15

  2.86

  2.50

  8.51

  4

  /

  3

  /

  7

  3

  1.03 2.36 0.412 ×

  1.06

  1.32

  3.25

  2.89

  9.82

  16

  /

  13

  16

  /

  2.09

  16

  /

  7.65

  1.01

  2.89

  1.82

  6.18

  4

  /

  1

  1.17 2.24 0.401 ×

  1.25

  1.25

  3.53

  2.25

  16

  1.14 1.81 0.368 L4×3×

  /

  5

  1.20 2.66 0.433 ×

  1.25

  1.48

  4.15

  2.68

  9.10

  8

  /

  3

  1.24 3.46 0.497 ×

  1.26

  5

  /

  1.87

  5

  1.27 2.60 0.683 ×

  1.26

  1.44

  3.94

  2.49

  8.47

  8

  /

  3

  1.32 3.36 0.747 ×

  1.24

  5.02

  /

  3.25

  11.1

  2

  /

  1

  1.37 4.08 0.810 ×

  1.23

  2.28

  6.01

  3.99

  13.6

  8

  11

  16

  1.92

  1.09

  1.13 1.67 0.633 ×

  1.11

  1.79 2.20 0.925

  6.10

  16

  /

  11

  16

  /

  5

  1.15 1.96 0.668 ×

  1.10

  2.56

  /

  2.12

  7.23

  4

  /

  3

  8

  /

  3

  1.20 2.52 0.736 ×

  1.08

  1.41

  3.24

  1

  4

  9.41

  /

  11/1/02

  /

  11

  4

  16 3 /

  /

  13

  16

  16 15 /

  /

  11

  4

  3

  5

  16

  /

  13

  16

  /

  15

  1.10 1.36 0.596

  1.12

  1.45 1.81 0.753

  4.94

  8

  /

  2.76

  8

  7.16

  3.02

  1.08

  1.29

  3.10

  2.67

  9.09

  16

  16 13 /

  7 /

  1.12 2.61 0.480 ×

  1.07

  1.45

  3.45

  10.3

  3 /

  8

  2 7 /

  1 / 2 ×3× 1 /

  1.70 2.00 0.787 1.09 0.954 1.41 0.243 L3

  5.79

  8

  /

  5

  4

  /

  1

  2.10 2.44 0.969 1.08 0.979 1.74 0.301 ×

  1.09 2.32 0.446 ×

  8 3 /

  2 7 /

  4 5 /

  1 /

  ×

  2

  1 /

  ×2

  2

  1 /

  1.02 1.39 0.336 L3

  1.10

  1.58 1.92 0.773

  5.38

  8

  1 /

  4

  1.05 1.72 0.375 ×

  1.09

  1.95 2.33 0.951

  6.65

  16

  16 11 /

  5 /

  1.07 2.03 0.411 ×

  1.09

  1.12

  2.73

  2.32

  7.88

  1.23

  5.30

  Angles (L-Shapes) Properties Shape k Wt. Area, A

  1.55

  2.89

  9.43

  3.75

  12.8

  16

  /

  15

  2

  /

  1

  1.55 2.78 0.868 L5×3×

  1.61

  5.36

  1.74

  2.07

  7.03

  16

  /

  11

  4

  /

  1

  1.57 3.45 0.901 ×

  1.60

  1.92

  6.58

  1.58

  5.12

  8.72

  1.21 ×

  1.69

  1.60

  2.22

  7.35

  2.86

  9.74

  16

  /

  13

  8

  /

  3

  4.53

  1.25 ×

  1.72

  1.59

  2.56

  8.41

  3.31

  11.3

  8

  /

  7

  16

  /

  7

  2.56

  4

  1.18 ×

  3 /

  1

  8

  5 /

  1.12 ×

  7.60

  1.74

  1.55

  4.26

  13.9

  5.82

  19.8

  16

  1

  /

  4

  3 /

  ×

  2

  1 /

  L5×3

  3 in.

  3 in. in. in.

  4 in.

  

2

in.

  I S r y Z y p in. lb/ft in.

  Axis X-X

  1

  16

  16 3 /

  2.97

  5 /

  1.60 4.09 0.933 ×

  1.59

  2.28

  7.75

  3.05

  10.4

  16

  8 13 /

  3 /

  1.65 5.33 0.997 ×

  1.58

  9.96

  16.8

  4.00

  13.6

  16

  2 15 /

  1 /

  1.06 ×

  6.50

  1.69

  1.56

  3.63

  12.0

  4.93

  3.93

  5

  3.50

  /

  /

  5

  1.13 2.69 0.357 ×

  1.23

  1.5

  4.32

  2.86

  9.72

  4

  /

  3

  8

  3

  11

  1.15 3.10 0.413 ×

  1.22

  1.73

  4.93

  3.30

  11.2

  16

  /

  13

  16

  /

  7

  16

  /

  1.21

  1.93

  11.9

  2

  /

  1

  ×

  2

  /

  1

  1.08 1.82 0.242 L4×3

  1.25

  1.03

  3.00

  6.58

  16

  8

  /

  5

  4

  /

  1

  1.11 2.26 0.300 ×

  1.24

  1.27

  3.67

  2.40

  8.16

  1.18 3.50 0.468 ×

  1.96

  /

  /

  1.12 L4×4×

  2.68

  1.64

  1.62

  1.51

  5.09

  1.94

  6.60

  16

  /

  11

  4

  1

  /

  1.15 ×

  3.32

  1.67

  1.61

  1.87

  6.24

  2.41

  8.19

  4

  /

  3

  16

  3

  4

  5.52

  4.61

  3.75

  12.7

  8

  /

  7

  2

  /

  1

  1.22 4.28 0.576 ×

  1.20

  2.38

  6.62

  15.7

  1

  1

  8

  /

  5

  1.27 5.02 0.679 ×

  1.18

  2.79

  7.62

  5.43

  18.5

  8

  /

  1

16 Rev.

DIMENSIONS AND PROPERTIES

  /

  /

  1

  1

  1

  All

  16 Permissible Variations in Length Shape Variations Over Specified Length for Lengths Given c , in. 5 to 10 ft, excl. 10 to 20 ft, excl. 20 to 30 ft, incl. Over 30 to 40 ft, incl. Over 40 to 65 ft, incl. Over 65 ft

  8 3 /

  16 1 / 8 1 /

  3 /

  32

  32 1 /

  5

  1

  8

  /

  1

  32

  /

  3

  8

  /

  1

  Over 7 to 14, incl.

  8 Channels

  2

  3

  1

  (total length, ft)

  11/1/02

  Rev.

  The tolerances herein are taken from ASTM A6 and apply to the straightness of members received from the rolling mill, mea- sured as illustrated in Figure 1-1. For tolerance on induced camber and sweep, see Code of Standard Practice Section 6.4.4.

  T + T ′ applies when flanges of channels are toed in or out. c The permitted variation under the specified length is 0 in. for all lengths. There are no requirements for lengths over 65 ft. d

  a A is measured at center line of web for beams and at back of web for channels. b

  64 in. per in. of depth.

  /

  1

  Ends Out of Square S-shapes, M-shapes and channels

  Other Permissible Rolling Variations Area and Weight ± 2.5 percent theoretical or specified amount.

  5 Sweep Due to the extreme variations in flexibility of these shapes, permitted variations for sweep are subject to negotiation between the manufacturer and purchaser for the individual sections involved.

  8 in.×

  /

  /

  1

  d Camber

  4

  /

  3

  2

  4

  /

  1

  2

  4

  /

  8

  1–151 Table 1-55.

  /

  8

  /

  1

  Over 7 to 14, incl.

  8 S-shapes and M-shapes

  /

  1

  8

  /

  1

  16

  1

  /

  32

  /

  3

  

Over Under Over Under

3 to 7, incl.

  E Web off Center, in.

  Flanges out of square, per in. of B, in.

  T + Tb

  B Flange width, in.

  A a Depth, in.

  Permissible Cross-Sectional Variations Shape Nominal, Depth, in.

  Back of square and centerline of web to be parallel when measuring “out-of-square”

  S-Shapes, M-Shapes, and Channels

  3

  32

  /

  /

  1

  16

  /

  1

  32

  /

  3

  16 3 to 7, incl.

  /

  3

  16

  3

  5

  8

  /

  1

  16

  /

  3

  16 Over 14 to 24, incl.

  32 1 / 32 3 /

  /

  5

  32

  /

  • – Over 14
  • Mill Straightness Tolerances
  • – indicates that there is no requirement.

  2–28 GENERAL DESIGN CONSIDERATIONS While still formally permitted in the LRFD Specification, the use of other material speci- fications in steel-to-steel structural bolting applications has become quite uncommon. ASTM

  A307 bolts are almost as infrequently specified today as are ASTM A501 and A502 rivets.

  Twist-Off-Type Tension-Control Bolt Assemblies As shown in Table 2-3, the preferred material specification for twist-off-type tension-control bolt assemblies is ASTM F1852, which offers a strength level that is equivalent to that of ASTM A325 bolts. When a higher strength is desired, twist-off-type tension-control bolt assemblies can be obtained in a strength level that is equivalent to that of ASTM A490 bolts using the provisions for alternative-design fasteners in RCSC Specification Section 2.8. In either case, Type 1 (medium-carbon steel) is most commonly specified. When atmospheric corrosion resistance is desired, Type 3 can be specified.

  Nuts As shown in Table 2-3, the preferred material specification for heavy-hex nuts is ASTM A563. The appropriate grade and finish is specified per ASTM A563 Table X1.1 according to the bolt or threaded part with which the nut will be used. For steel-to-steel structural bolting applications, the appropriate grade and finish is summarized in RCSC Specification Section

  2.4. If its availability can be confirmed prior to specification, ASTM A194 grade 2H nuts are permitted as an alternative as indicated in RCSC Specification Table 2.1.

  Washers As shown in Table 2-3, the preferred material specification for hardened steel washers is ASTM F436. This specification provides for both flat and beveled washers. While standard ASTM F436 washers are sufficient in most applications, there are several specific applications when special washers are required. The special washer requirements in RCSC Specification Section 6 apply when oversized or slotted holes are used in the outer ply of a steel-to-steel structural joint. In anchor rod and other embedment applications, hole sizes are generally larger than those for steel-to-steel structural bolting applications (see Table 14-2 for maxi- mum anchor-rod hole sizes). Accordingly, washers used in such applications are generally larger and may require design consideration for proper force transfer, particularly when the Rev. anchorage is subject to tension. See Table 14-2 for anchor-rod washer sizes.

  11/1/02 Compressible-Washer-Type Direct-Tension Indicators When bolted joints are specified as pretensioned or slip-critical and the direct-tension- indicator pretensioning method is used, ASTM F959 compressible-washer-type direct-tension indicators are specified, as shown in Table 2-3. Type 325 is used with ASTM A325 high- strength bolts and type 490 is used with ASTM A490 high-strength bolts.

  Anchor Rods As shown in Table 2-3, the preferred material specification for anchor rods is ASTM F1554, which covers hooked, headed and threaded and nutted anchor rods in three strength grades: 36, 55 and 105. ASTM F1554 grade 36 is most commonly specified, although grades 55 and 105 are normally available, albeit with potentially longer lead times, when higher strength is required. ASTM F1554 grade 36 or ASTM F1554 grade 55 with weldability supplement S1 and the carbon equivalent formula in ASTM F1554 Section S1.5.2.1 can be specified to allow welded field correction should the anchor rods be placed incorrectly in the field. ASTM F1554 grades 36, 55 and 105 are essentially the anchor-rod equivalents of the generic rod specifications ASTM A36, ASTM A572 grade 55 and A193 grade B7, respectively. FIRE PROTECTION AND ENGINEERING 2–47 Table 2-10.

  Construction Classification, Restrained and Unrestrained Single-span Open-web steel joists or steel beams, supporting concrete slab, unrestrained and simply precast units, or metal decking supported end spans of multiple unrestrained Concrete slabs, precast units, or metal decking a bays

  Open-web steel joists, steel beams or metal decking, supporting restrained continuous concrete slab Open-web steel joists or steel beams, supporting precast units or

  Wall Bearing Interior spans unrestrained metal decking of multiple bays

  Cast-in-place concrete slab systems restrained Precast concrete where the potential thermal expansion is resisted restrained

  b

  by adjacent construction Steel beams welded, riveted, or bolted to the framing members restrained All types of cast-in-place floor and roof systems (such as beam-and-slabs, flat slabs, pan joists, and waffle slabs) where the restrained floor or roof system is secured to the framing members

  Steel All types of prefabricated floor or roof systems where the structural

  Framing members are secured to the framing members and the potential thermal expansion of the floor or roof system is resisted restrained by the framing system or the adjoining floor or roof

  b

  construction Beams securely fastened to the framing members restrained All types of cast-in-place floor and roof systems (such as beam-and-slabs, flat slabs, pan joists, and waffle slabs) where the restrained floor system is cast with the framing members Interior and exterior spans of precast systems with cast-in-place

  Concrete joints resulting in restraint equivalent to that which would restrained

  b(i)

  Framing exist in [concrete framing] All types of prefabricated floor or roof systems where the structural members are secured to such systems and the potential thermal Rev. expansion of the floor or roof systems is restrained

  11/1/02 resisted by the framing system or the adjoining floor or roof

  b

  construction Wood

  All types unrestrained

  Construction

  a

  Floor and roof system scan be considered restrained when they are tied into walls or without tie beams, the walls being designed and detailed to resist thermal thrust from the floor or roof system.

  b

  For example, resistance to potential thermal expansion is considered to be achieved when: (i) Continuous structural concrete topping is used, (ii) The space between the ends of precast units or between the ends of units and the vertical face of supports is filled with concrete or mortar, or

  (iii) The space between the ends of precast units and the vertical faces of supports, or between the ends of solid or hollow core slab units does not exceed 0.25% of the length for normal weight concrete members of 0.1% of the length for structural light weight concrete members. From ASTM E119-2000 Table X 3.1. Copyright ASTM. Reprinted with permission.

DESIGN EXAMPLES

  3–7

  2 design strength with A e g is tabulated as 259 kips.

  = 0.75A = 5.31 in.

  A

e

  P φ t n

  = 259 kips

0.75 A g

  2 5.11 in.

  = 259 kips

  2

5.31 in.

  = 249 kips Similarly, for solution b,

  2 A e 5.68 in.

  =

  2 A g 7.08 in.

  = 0.802 < 0.923 Therefore, tension rupture controls. For tension rupture, the W8×24 de- 2 sign strength with A e g is tabulated as 259 kips.

  = 0.75A = 5.31 in.

  A

e

  P φ t n

  = 259 kips

0.75 A g

  2 5.68 in.

  = 259 kips

  2

5.31 in.