1. 1525 Wilson Boulevard, Suite 600, Arlington, VA 22209
2. Copyright June 2005, The Aluminum Association, Inc. All
rights reserved No part of this publication may be reproduced,
stored in a retrieval system, or transmitted, in any form, or by
any means, electronic, mechanical, photocopying, recording, or
otherwise, without the prior written permission of The Aluminum
Association, Inc.
3. TABLE OF CONTENTS
4. Aluminum Design Manual Table of Contents PART TITLE IA
Specication for Aluminum Structures Allowable Stress Design IB
Specication for Aluminum Structures Building Load and Resistance
Factor Design IIA Commentary on Specication for Aluminum Structures
Allowable Stress Design IIB Commentary on Specication for Aluminum
Structures Building Load and Resistance Factor Design III Design
Guide IV Materials V Material Properties VI Section Properties VII
Design Aids VIII Illustrative Examples of Design IX Guidelines for
Aluminum Sheet Metal Work in Building Construction Appendix 1
Metric Guide for Aluminum Structural Design Index
5. FOREWORD
6. FOREWORD The Aluminum Design Manual includes aluminum
structural design specications and accompanying commentary, a
supplemental design guide, material properties, section properties,
design aid tables and graphs, illustrative design examples and
guidelines for aluminum sheet metal work in building construction.
This edition of the Aluminum Design Manual is the product of the
efforts of the Aluminum Association Engineering and Design Task
Force, whose members are listed below. The Aluminum Association
Engineering and Design Task Force Steve Sunday, Alcoa Inc., chair
Frank Armao, Lincoln Electric Co. Randy Killian, Conservatek
Industries, Inc. Randy Kissell, The TGB Partnership Greg McKenna,
Kawneer Company, Inc. Craig C. Menzemer, University of Akron George
Olive, Larson Engineering of Missouri Gerald Orrison, Temcor Teoman
Pekz, Cornell University Frank Shoup, Alcoa Inc. Mike Skillingberg,
The Aluminum Association, Inc.
7. Check www.aluminum.org for ADM 2005 updates.
8. Aluminum Design Manual PART I-A Specication for Aluminum
Structures Allowable Stress Design The Aluminum Association, Inc.
1525 Wilson Boulevard, Suite 600, Arlington, VA 22209 Eighth
Edition, January 2005
9. January 2005 I-A-3 FOREWORD The rst edition of the
Specication for Aluminum Structures was published in November,
1967, followed by subsequent edi- tions in 1971, 1976, 1982, 1986,
1994, and 2000. This eighth edition of the allowable stress design
Specication, developed as a consensus document, includes new or
revised provisions concerning shear yield strengths welded
strengths adding 6063-T52, 6351-T6, and 7005-T53 materials for
screws used to connect aluminum parts factors on welded tensile
ultimate strength and compressive yield strength welded connections
(groove, llet, plug and slot, and stud welds) screw pull-over
revision of Section 1.2, Materials revision of Section 5,
Mechanical Connections revision of Section 6, Fabrication and
Erection a new Section 8, Castings weighted average strengths
design stresses for wind loads fatigue strength for welds with
permanent backing net effective areas for channels, I beams, zees,
angles, and tees single angles in exure tapered thickness element
strength web crippling of extrusions compressive strength of
complex cross sections strength of elements in bending in their own
plane unbraced length in bending These improvements and additions
are the result of studies sponsored by the Aluminum Association and
others. The Aluminum Association gratefully acknowledges the
efforts of the Engineering and Design Task Force in drafting this
Specication and the Engineering Advisory Committee in reviewing it.
The Aluminum Association Engineering and Design Task Force Steve
Sunday, Alcoa Inc., chair Frank Armao, Lincoln Electric Co. Randy
Killian, Conservatek Industries, Inc. Randy Kissell, The TGB
Partnership Greg McKenna, Kawneer Company, Inc. Craig C. Menzemer,
University of Akron George Olive, Larson Engineering of Missouri
Gerald Orrison, Temcor Teoman Pekz, Cornell University Frank Shoup,
Alcoa Inc. Mike Skillingberg, The Aluminum Association, Inc. The
Aluminum Association Engineering Advisory Committee Includes the
members of the Engineering and Design Task force and the following
persons: Robert E. Abendroth, Iowa State University Francisco
Castano, Geometrica, Inc. Terence Cavanagh, Terrapin Testing, Inc.
Karen C. Chou, Minnesota State University, Mankato Cynthia Ebert,
Larson Engineering of Missouri
10. I-A-4 November 2005 Andrew J. Hinkle, S & K
Technologies Dimitris Kosteas, Technical University of Munich LeRoy
Lutz, Computerized Structural Design Brian Malloy, Alcoa Engineered
Products Ray Minor, Hapco American Flag Carl Wagus, American
Architectural Manufacturers Association Robert W. Walton, Texas
Wall Systems Guidelines for the Preparation of Technical Inquiries
on the Specication for Aluminum Structures Technical inquiries to
obtain an interpretation or request a revision to the Specication
for Aluminum Structures should be directed to: VP, Technology The
Aluminum Association 1525 Wilson Blvd. Suite 600 Arlington, VA
22209 Fax: 703-358-2961 email: [email protected] Comments on
other parts of the Aluminum Design Manual are also welcome.
Inquiries should be typewritten and include the inquirers name,
afliation, and address. Each inquiry should address a single
section of the Specication unless the inquiry involves two or more
interrelated sections. The section and edition of the Speci- cation
should be identied. Requests for interpretations should be phrased,
where possible, to permit a yes or no answer and include the
necessary background information, including sketches where
appropriate. Requests for revisions should include proposed wording
for the revision and technical justication. Inquiries are
considered at the rst meeting of the Engineering and Design Task
Force following receipt of the inquiry.
15. January 2005 I-A-9 Section 1. General 1.1 Scope This
Specication shall apply to the design of aluminum alloy
load-carrying members. 1.2 Materials This Specication applies to
the aluminum alloys listed in Tables 3.3-1, 5.2.3-1, and 5.3.4-1
and produced to the following ASTM specications: B 209 Aluminum and
Aluminum-Alloy Sheet and Plate B 210 Aluminum and Aluminum-Alloy
Drawn Seam- less Tubes B 211 Aluminum and Aluminum-Alloy Bar, Rod,
and Wire B 221 Aluminum and Aluminum-Alloy Extruded Bars, Rods,
Wire, Proles, and Tubes B 241 Aluminum and Aluminum-Alloy Seamless
Pipe and Seamless Extruded Tube B 247 Aluminum and Aluminum-Alloy
Die Forgings, Hand Forgings, and Rolled Ring Forgings B 308
Aluminum-Alloy 6061-T6 Standard Structural Proles B 316 Aluminum
and Aluminum-Alloy Rivet and Cold-Heading Wire and Rods B 429
Aluminum Alloy Extruded Structural Pipe and Tube B 632 Aluminum
Alloy Rolled Tread Plate B 928 High Magnesium Aluminum-Alloy Sheet
and Plate for Marine Service F 468 Nonferrous Bolts, Hex Cap
Screws, and Studs for General Use This Specication also applies to
castings that meet the requirements of Section 8.1. 1.3 Safety
Factors 1.3.1 Building Type Structures Basic allowable tensile
stresses for buildings, structural supports for highway signs,
luminaires, trafc signals, and similar structures shall be the
lesser of the minimum yield strength divided by a factor of safety
of 1.65, or the mini- mum ultimate tensile strength divided by a
factor of safety of 1.95. Other allowable stresses for buildings
and similar structures shall be based upon the factors of safety
shown in Table 3.4-1. 1.3.2 Bridge Type Structures Basic allowable
tensile stresses for bridge type structures shall be the lesser of
the minimum yield strength divided by a factor of safety of 1.85,
or the minimum ultimate tensile strength divided by a factor of
safety of 2.2. Other allow- able stresses for bridge and similar
structures shall be based upon the factors of safety shown in Table
3.4-1. 1.3.3 Other Type Structures Where it is customary or
standard practice to use factors of safety other than those given
in Sections 1.3.1 or 1.3.2, the general formulas in Table 3.4-3
shall be permitted to be used with the desired factors of safety
substituted for nu, ny, or na.
16. I-A-10 January 2005 Section 2. Design Procedure 2.1 Section
Properties Section properties such as cross-sectional area, moment
of inertia, section modulus, radius of gyration, and torsion and
warping constants shall be determined using nominal dimensions.
Cross section dimensions shall not vary by more than the tolerances
given in Aluminum Standards and Data. 2.2 Procedure Computations of
forces, moments, stresses, and deec- tions shall be in accordance
with accepted methods of elas- tic structural analysis and
engineering design. The formu- las and methods for determining
allowable stresses in this Specication have been simplied in many
cases for ease of computation but are not intended to preclude the
use of more rigorous analysis. 2.3 Loads Building-type structures
shall be designed for the nomi- nal loads given in the applicable
building code or perfor- mance specication. Nominal loads shall be
factored and combined in accordance with the applicable building
code or performance specication. In the absence of a code or
performance specication, ASCE 7-02, Minimum Design Loads for
Buildings and Other Structures, shall be used. Bridge-type
structures shall be designed for the loads given in AASHTOs
Standard Specications for Highway Bridges. Other structures shall
be designed for the loads given in the performance
specication.
17. January 2005 I-A-11 Section 3. General Design Rules 3.1
Material Properties Minimum mechanical properties used for
non-welded material shall be as listed in Table 3.3-1. Minimum
mechanical properties used for welded material shall be as listed
in Table 3.3-2. The following properties shall be used unless more
pre- cise values are specied: Coefcient of thermal expansion 13
10-6 /o F (23 10-6 /o C) Density 0.1 lb/in3 (2.7 103 kg/m3 )
Poissons ratio 0.33 3.2 Nomenclature A consistent set of units
shall be used throughout this Specication. a = detail dimension
parallel to the direction of stress ae = equivalent width of
rectangular panel al = shorter dimension of rectangular panel a2 =
longer dimension of rectangular panel A = cross sectional area Ac =
area of compression element (compression ange plus 1 /3 of area of
web between compression ange and neutral axis) Ah = gross area of
cross section of longitudinal stiffener As = area of the stiffener
Asn = thread stripping area of internal thread per unit length of
engagement Aw = the portion of area of cross section A lying within
1.0 in. (25 mm) of a weld b = width of section or element be =
effective width of at element to be used in deection calculations
bo = width of element with an intermediate stiffener as shown in
Fig. 3.4.9.2-1 b/t = width to thickness ratio of a at element of a
cross section B = buckling formula intercept with the following
subscripts: c-compression in columns p-compression in at elements
t-compression in curved elements tb-bending in curved elements
br-bending in at elements s-shear in at elements c = distance from
neutral axis to extreme ber C = buckling formula intersection (see
B for subscripts) C = coefcient which depends on screw location Cb
= coefcient which depends on moment gradient Cf = constant to be
determined from Table 4.8.1-1 and Figure 4.8.1-1 Cm = 0.6 -
0.4(M1/M2) for members whose ends are prevented from sway = 0.85
for members whose ends are not prevented from swaying CP =
correction factor Cw = torsional warping constant of the cross
section Cwa = t2 sin (0.46Fcy + 0.02 ____ EFcy) Cwb = Cw3 + Ri
(1cos) Cw1 = 5.4 in. (140 mm) Cw2 = 1.3 in. (33 mm) Cw3 = 0.4 in.
or 10 mm consistent with other units used C1 = coefcient dened in
Section 4.9.4 C2 = coefcient dened in Section 4.9.4 d = depth of
section or beam df = distance between ange centroids ds = at width
of lip stiffener shown in Fig. 3.4.9.1-1 d1 = clear distance from
the neutral axis to the compression ange D = buckling formula slope
(see B for subscripts) D = diameter Dh = nominal hole diameter Dn =
nominal dead load Ds = dened in Fig. 3.4.9.1-1 Dw = nominal washer
diameter Dws = larger of the nominal washer diameter and the screw
head e = base for natural logarithms 2.72 E = compressive modulus
of elasticity (See Table 3.3-1) f = calculated stress fa = average
stress on cross section produced by axial load fb = maximum bending
stress produced by transverse loads and/or bending moment fs =
shear stress caused by torsion or transverse shear loads F =
allowable stress Fa = allowable compressive stress for a member
con- sidered as an axially loaded column according to Sections
3.4.7 through 3.4.10 Fao = allowable compressive stress of axially
loaded member considered as a short column according to Section
4.7.2. Fb = allowable bending stress for members subjected to
bending only Fc = allowable compressive stress Fcr = local buckling
stress for element from Section 4.7.1 Fcy = compressive yield
strength Fcyw = compressive yield strength across a groove weld
(0.2% offset in 2 in. (50 mm) gage length) Fe = elastic buckling
stress divided by nu = 2 E_______ nu(kL/r)2
18. I-A-12 January 2005 Feb = elastic lateral buckling stress
of beam calculated using Eq. 3.4.11-3 or Section 4.9 with ny = 1.0
Fec = elastic critical stress Fec = allowable elastic lateral
buckling stress of beam calculated assuming that the elements are
not buckled Fef = elastic torsional-exural buckling stress Fet =
elastic torsional buckling stress Fet = 1____ Ar 2 O (GJ + 2
ECw______ (KtLt)2 ) Fex = 2 E______ (kxLb____ rx )2 Fm = mean value
of the fabrication factor Fn = allowable stress for cross section
1.0 in. (25 mm) or more from weld Fpw = allowable stress on cross
section, part of whose area lies within 1.0 in. (25 mm) of a weld
Frb = allowable stress for beam with buckled elements Frc =
allowable stress for column with buckled elements Fs = allowable
shear stress for members subjected only to torsion or shear FST =
allowable stress according to Section 3.4.9.1 or 3.4.16.2 Fsu =
shear ultimate strength Fsuw = shear ultimate strength within 1.0
in. (25 mm) of a weld Ft = allowable tensile stress for the member
loaded only axially according to Section 3.4.1 Ftu = tensile
ultimate strength Ftuw = tensile ultimate strength across a groove
weld Ftul = tensile ultimate strength of member in contact with the
screw head Ftu2 = tensile ultimate strength of member not in
contact with the screw head Fty = tensile yield strength Ftyw =
tensile yield strength across a groove weld (0.2% offset in 2 in.
(50 mm) gage length) FUT = allowable stress according to Section
3.4.9.1 or 3.4.16.2 Fw = allowable stress on cross section if
entire area were to lie within 1.0 in. (25 mm) of a weld Fy =
either Fty or Fcy, whichever is smaller g = spacing of rivet or
bolt holes perpendicular to direction of load go = distance from
shear center to the point of application of load G = shear modulus
Gf = grip of rivet or bolt h = clear height of shear web I = moment
of inertia Ib = required moment of inertia of bearing stiffener Icy
= moment of inertia of compression ange about web Ih = moment of
inertia of longitudinal stiffener Io = moment of inertia of the
stiffener about the cen- troidal axis of the stiffener parallel to
the at element that is stiffened Is = moment of inertia of
transverse stiffener to resist shear buckling Ix = moment of
inertia of a beam about axis perpendicular to web Iy = moment of
inertia of a beam about axis parallel to web Iyc = moment of
inertia of compression element about axis parallel to vertical web
j = parameter dened by Eq. 4.9.3-5 or -6 J = torsion constant k =
the effective length factor. k shall be taken larger than or equal
to unity unless rational analysis justies a smaller value kt =
coefcient for tension members kx = effective length coefcient for
buckling about the x-axis ky = effective length coefcient for
buckling about the y-axis kl = coefcient for determining
slenderness limit S2 for sections for which the allowable
compressive stress is based on ultimate strength k2 = coefcient for
determining allowable compres- sive stress in sections with
slenderness ratio above S2 for which the allowable compressive
stress is based on ultimate strength Ks = coefcient in Section
5.4.2.1 Kt = effective length coefcient for torsional buckling. Kt
shall be taken larger than or equal to unity unless rational
analysis justies a smaller value L = unsupported length in the
plane of bending Lb = unbraced length for bending Ln = nominal live
load Ls = length of tube between circumferential stiffeners Lt =
unbraced length for twisting m = constant to be determined from
Table 4.8.1-1 M = bending moment applied to the member Ma =
allowable bending moment for the member if bending moment alone is
applied to the member MA = absolute value of moment at
quarter-point of the unbraced beam segment MB = absolute value of
moment at mid-point of the unbraced beam segment MC = absolute
value of moment at three-quarter point of the unbraced beam segment
Me = elastic critical moment Mi = bending strength of member with
intermediate thickness Mm = mean value of the material factor MMAX
= absolute value of maximum moment in the unbraced beam segment M1
= bending strength of member of thinnest material M2 = bending
strength of member of thickest material
19. January 2005 I-A-13 M1/M2 = ratio of end moments where M2
is the larger of the two end moments and M1/M2 is positive when the
member is bent in reverse curvature, negative when bent in single
curvature n = number of tests n = number of threads per unit length
for a screw na = factor of safety on appearance of buckling ns =
factor of safety for screw connections nu = factor of safety on
ultimate strength ny = factor of safety on yield strength N =
length of bearing at reaction or concentrated load N = number of
cycles to failure Ns = number of stress ranges in the spectrum P =
applied interior reaction or concentrated load per web for at webs
Pas = allowable shear force per screw Pat = allowable tensile force
per screw Pbs = concentrated load on bearing stiffener Pc =
allowable reaction or concentrated load per web Pnot = nominal
pull-out strength per screw Pnov = nominal pull-over strength per
screw Pns = nominal shear strength per screw Pnt = nominal tensile
strength per screw q = uniform design load r = radius of gyration
ro = _______________ r 2 x + r 2 y + x 2 o + y 2 o rs = radius of
gyration of the stiffener rx , ry = radii of gyration of the
cross-section about the cen- troidal principal axes (see Section
4.9.2 for rye of singly symmetric sections unsymmetric about the
bending axis) rye = effective radius of gyration R = transition
radius, the radius of an attachment of the weld detail Rb =
mid-thickness radius of a round element or maxi- mum mid-thickness
radius of an oval element Ri = bend radius at juncture of ange and
web measured to inside surface of bend Rs = stress ratio, the ratio
of minimum stress to maximum stress s = spacing of transverse
stiffeners (clear distance between stiffeners for stiffeners
consisting of a pair of members, one on each side of the web,
center-to-center distance between stiffeners con- sisting of a
member on one side of the web only); spacing of rivet or bolt holes
parallel to direction of load S = 1.28 ___ E___ Fcy Sc = section
modulus of a beam, compression side Sra = the applied stress range
Srd = allowable stress range Sre = equivalent stress range Sri =
the ith stress range in the spectrum St = section modulus of a
beam, tension side Sw = size of a weld Sx = standard deviation of
the test results S1, S2 = slenderness limits t = thickness of
element tavg = the average thickness of the element tc = depth of
full thread engagement of screw into t2 not including tapping or
drilling point ti = thickness of the intermediate thickness
material tested tmax = thickness of thickest material tested tmax =
greater thickness of a tapered thickness element tmin = thickness
of thinnest material tested tmin = lesser thickness of a tapered
thickness element t1 = thickness of member in contact with the
screw head t2 = thickness of member not in contact with the screw
head U = parameter dened by Eq. 4.9.3-8 V = shear force on web at
stiffener location VF = coefcient of variation of the fabrication
factor VM = coefcient of variation of the material factor VP =
coefcient of variation of the ratio of the observed failure loads
divided by the average value of all the observed failure loads VQ =
coefcient of variation of the loads xo = x - coordinate of the
shear center Xa = strength at which 99% of the material is expected
to conform at a condence level of 95% Xi = failure load of ith test
Xm = mean of the test results yo = y - coordinate of the shear
center = Dn /Ln i = number of cycles in the spectrum of the ith
stress range divided by the total number of cycles s = a factor
equal to unity for a stiffener consisting of equal members on both
sides of the web and equal to 3.5 for a stiffener consisting of a
mem- ber on one side only = 1 (xo /ro)2 o = the target reliability
index s = spring constant (transverse force applied to the
compression ange of the member of unit length divided by the
deection due to the force) = (tmax tmin)_________ tmin for tapered
thickness elements s = equivalent slenderness ratio for an
intermediate stiffener st = ratio dened in Section 3.4.9.1 and
3.4.16.2 = angle between plane of web and plane of bearing surface
( 90)
20. I-A-14 January 2005 3.3 Tables Relating to Mechanical
Properties and Buckling Constants This Section consists of the
following tables concerning formulas for determining allowable
stresses and constants and coefcients needed for these formulas:
3.3-1 Minimum Mechanical Properties for Alumi- num Alloys 3.3-1M
Minimum Mechanical Properties for Alumi- num Alloys 3.3-2 Minimum
Mechanical Properties for Welded Aluminum Alloys 3.3-2M Minimum
Mechanical Properties for Welded Aluminum Alloys 3.3-3 Formulas for
Buckling Constants for Prod- ucts Whose Temper Designation Begins
With -O, -H, -T1, -T2, T3, or -T4 3.3-4 Formulas for Buckling
Constants for Prod- ucts Whose Temper Designation Begins With -T5,
-T6, -T7, -T8, or -T9
21. January 2005 I-A-15 Table 3.3-1 MINIMUM MECHANICAL
PROPERTIES FOR ALUMINUM ALLOYS ALLOY AND TEMPER PRODUCT THICKNESS
RANGE in. Ftu ksi Fty ksi Fcy ksi Fsu ksi COMPRESSIVE MODULUS OF
ELASTICITY2 E (ksi) 1100-H12 -H14 Sheet, Plate, Drawn Tube, Rolled
Rod & Bar All All 14 16 11 14 10 13 9 10 10,100 10,100 2014-T6
-T651 -T6, T6510, T6511 -T6, T651 Sheet Plate Extrusions Cold
Finished Rod & Bar, Drawn Tube 0.040 to 0.249 0.250 to 2.000
All All 66 67 60 65 58 59 53 55 59 58 52 53 40 40 35 38 10,900
10,900 10,900 10,900 Alclad 2014-T6 -T6 -T651 Sheet Sheet Plate
0.025 to 0.039 0.040 to 0.249 0.250 to 0.499 63 64 64 55 57 57 56
58 56 38 39 39 10,800 10,800 10,800 3003-H12 -H14 -H16 -H18 -H12
-H14 -H16 -H18 Sheet & Plate Sheet & Plate Sheet Sheet
Drawn Tube Drawn Tube Drawn Tube Drawn Tube 0.017 to 2.000 0.009 to
1.000 0.006 to 0.162 0.006 to 0.128 All All All All 17 20 24 27 17
20 24 27 12 17 21 24 12 17 21 24 10 14 18 20 11 16 19 21 11 12 14
15 11 12 14 15 10,100 10,100 10,100 10,100 10,100 10,100 10,100
10,100 Alclad 3003-H12 -H14 -H16 -H18 -H14 -H18 Sheet & Plate
Sheet & Plate Sheet Sheet Drawn Tube Drawn Tube 0.017 to 2.000
0.009 to 1.000 0.006 to 0.162 0.006 to 0.128 0.025 to 0.259 0.010
to 0.500 16 19 23 26 19 26 11 16 20 23 16 23 9 13 17 19 15 20 10 12
14 15 12 15 10,100 10,100 10,100 10,100 10,100 10,100 3004-H32 -H34
-H36 -H38 -H34 -H36 Sheet & Plate Sheet & Plate Sheet Sheet
Drawn Tube Drawn Tube 0.017 to 2.000 0.009 to 1.000 0.006 to 0.162
0.006 to 0.128 0.018 to 0.450 0.018 to 0.450 28 32 35 38 32 35 21
25 28 31 25 28 18 22 25 29 24 27 17 19 20 21 19 20 10,100 10,100
10,100 10,100 10,100 10,100 Alclad 3004-H32 -H34 -H36 -H38 -H131,
H241, H341 -H151, H261, H361 Sheet Sheet Sheet Sheet Sheet Sheet
0.017 to 0.249 0.009 to 0.249 0.006 to 0.162 0.006 to 0.128 0.024
to 0.050 0.024 to 0.050 27 31 34 37 31 34 20 24 27 30 26 30 17 21
24 28 22 28 16 18 19 21 18 19 10,100 10,100 10,100 10,100 10,100
10,100 3005-H25 -H28 Sheet Sheet 0.013 to 0.050 0.006 to 0.080 26
31 22 27 20 25 15 17 10,100 10,100 3105-H25 Sheet 0.013 to 0.080 23
19 17 14 10,100 5005-H12 -H14 -H16 -H32 -H34 -H36 Sheet & Plate
Sheet & Plate Sheet Sheet & Plate Sheet & Plate Sheet
0.017 to 2.000 0.009 to 1.000 0.006 to 0.162 0.017 to 2.000 0.009
to 1.000 0.006 to 0.162 18 21 24 17 20 23 14 17 20 12 15 18 13 15
18 11 14 16 11 12 14 11 12 13 10,100 10,100 10,100 10,100 10,100
10,100 5050-H32 -H34 -H32 -H34 Sheet Sheet Cold Fin. Rod & Bar
Drawn Tube Cold Fin. Rod & Bar Drawn Tube 0.017 to 2.000 0.009
to 0.249 All All 22 25 22 25 16 20 16 20 14 18 15 19 14 15 13 15
10,100 10,100 10,100 10,100 For all footnotes, see last page of
this Table. ( )
22. Table 3.3-1 MINIMUM MECHANICAL PROPERTIES FOR ALUMINUM
ALLOYS ALLOY AND TEMPER PRODUCT THICKNESS RANGE in. Ftu ksi Fty ksi
Fcy ksi Fsu ksi COMPRESSIVE MODULUS OF ELASTICITY2 E (ksi) 5052-O
-H32 -H34 -H36 Sheet & Plate Sheet & Plate Cold Fin. Rod
& Bar Drawn Tube Sheet 0.006 to 3.000 All All 0.006 to 0.162 25
31 34 37 9.5 23 26 29 9.5 21 24 26 16 19 20 22 10,200 10,200 10,200
10,200 5083-O -H111 -H111 -O -H116 -H32, H321 -H116 -H32, H321
Extrusions Extrusions Extrusions Sheet & Plate Sheet &
Plate Sheet & Plate Plate Plate up thru 5.000 up thru 0.500
0.501 to 5.000 0.051 to 1.500 0.188 to 1.500 0.188 to 1.500 1.501
to 3.000 1.501 to 3.000 39 40 40 40 44 44 41 41 16 24 24 18 31 31
29 29 16 21 21 18 26 26 24 24 24 24 23 25 26 26 24 24 10,400 10,400
10,400 10,400 10,400 10,400 10,400 10,400 5086-O -H111 -H111 -O
-H112 -H112 -H112 -H112 -H116 -H32 -H34 Extrusions Extrusions
Extrusions Sheet & Plate Plate Plate Plate Plate Sheet &
Plate Sheet & Plate Drawn Tube Sheet & Plate Drawn Tube up
thru 5.000 up thru 0.500 0.501 to 5.000 0.020 to 2.000 0.025 to
0.499 0.500 to 1.000 1.001 to 2.000 2.001 to 3.000 All All All 35
36 36 35 36 35 35 34 40 40 44 14 21 21 14 18 16 14 14 28 28 34 14
18 18 14 17 16 15 15 26 26 32 21 21 21 21 22 21 21 21 24 24 26
10,400 10,400 10,400 10,400 10,400 10,400 10,400 10,400 10,400
10,400 10,400 5154-H38 Sheet 0.006 to 0.128 45 35 33 24 10,300
5454-O -H111 -H111 -H112 -O -H32 -H34 Extrusions Extrusions
Extrusions Extrusions Sheet & Plate Sheet & Plate Sheet
& Plate up thru 5.000 up thru 0.500 0.501 to 5.000 up thru
5.000 0.020 to 3.000 0.020 to 2.000 0.020 to 1.000 31 33 33 31 31
36 39 12 19 19 12 12 26 29 12 16 16 13 12 24 27 19 20 19 19 19 21
23 10,400 10,400 10,400 10,400 10,400 10,400 10,400 5456-O -H116
-H32, H321 -H116 -H32, H321 -H116 -H32, H321 Sheet & Plate
Sheet & Plate Sheet & Plate Plate Plate Plate Plate 0.051
to 1.500 0.188 to 1.250 0.188 to 1.250 1.251 to 1.500 1.251 to
1.500 1.501 to 3.000 1.501 to 3.000 42 46 46 44 44 41 41 19 33 33
31 31 29 29 19 27 27 25 25 25 25 26 27 27 25 25 25 25 10,400 10,400
10,400 10,400 10,400 10,400 10,400 6005-T5 Extrusions up thru 1.000
38 35 35 24 10,100 6061-T6, T651 -T6, T6510, T6511 -T6, T651 -T6
-T6 Sheet & Plate Extrusions Cold Fin. Rod & Bar Drawn Tube
Pipe 0.010 to 4.000 All up thru 8.000 0.025 to 0.500 All 42 38 42
42 38 35 35 35 35 35 35 35 35 35 35 27 24 25 27 24 10,100 10,100
10,100 10,100 10,100 6063-T5, -T52 -T5 -T6 Extrusions Extrusions
Extrusions Extrusions & Pipe up thru 0.500 up thru 1.000 0.500
to 1.000 All 22 22 21 30 16 16 15 25 16 16 15 25 13 13 12 19 10,100
10,100 10,100 10,100 6066-T6, T6510, T6511 Extrusions All 50 45 45
27 10,100 6070-T6, T62 Extrusions up thru 2.999 48 45 45 29 10,100
6105-T5 Extrusions up thru 0.500 38 35 35 24 10,100 6351 6351 -T5
-T6 Extrusions Extrusions up thru 1.000 up thru 0.750 38 42 35 37
35 37 24 27 10,100 10,100 6463-T6 Extrusions up thru 0.500 30 25 25
19 10,100 7005-T53 Extrusions up thru 0.750 50 44 43 28 10,500 1.
Ftu and Fty are minimum specied values (except Fty for 1100-H12,
H14 Cold Finished Rod and Bar and Drawn Tube, Alclad 3003-H18 Sheet
and 5050-H32, H34 Cold Finished Rod and Bar which are minimum
expected values); other strength properties are corresponding
minimum expected values. 2. Typical values. For deection
calculations an average modulus of elasticity is used; this is 100
ksi lower than values in this column. ( ) I-A-16 May 2005
23. January 2005 I-A-17 Table 3.3-1M MINIMUM MECHANICAL
PROPERTIES FOR ALUMINUM ALLOYS ALLOY AND TEMPER PRODUCT THICKNESS
RANGE mm Ftu MPa Fty MPa Fcy MPa Fsu MPa COMPRESSIVE MODULUS OF
ELASTICITY2 E (MPa) 1100-H12 -H14 Sheet, Plate, Drawn Tube, Rolled
Rod & Bar All All 95 110 75 95 70 90 62 70 69,600 69,600
2014-T6 -T651 -T6, T6510, T6511 -T6, T651 Sheet Plate Extrusions
Cold Finished Rod & Bar, Drawn Tube 1.00 to 6.30 6.30 to 50.00
All All 455 460 415 450 400 405 365 380 405 400 360 365 275 275 240
260 75,200 75,200 75,200 75,200 Alclad 2014-T6 -T6 -T651 Sheet
Sheet Plate 0.63 to 1.00 1.00 to 6.30 6.30 to 12.50 435 440 440 380
395 395 385 400 385 260 270 270 74,500 74,500 74,500 3003-H12 -H14
-H16 -H18 -H12 -H14 -H16 -H18 Sheet & Plate Sheet & Plate
Sheet Sheet Drawn Tube Drawn Tube Drawn Tube Drawn Tube 0.40 to
50.00 0.20 to 25.00 0.15 to 4.00 0.15 to 3.20 All All All All 120
140 165 185 120 140 165 185 85 115 145 165 85 115 145 165 70 95 125
140 75 110 130 145 75 85 95 105 75 85 95 105 69,600 69,600 69,600
69,600 69,600 69,600 69,600 69,600 Alclad 3003-H12 -H14 -H16 -H18
-H14 -H18 Sheet & Plate Sheet & Plate Sheet Sheet Drawn
Tube Drawn Tube 0.40 to 50.00 0.20 to 25.00 0.15 to 4.00 0.15 to
3.20 0.63 to 6.30 0.25 to 12.50 115 135 160 180 135 180 80 110 140
160 110 160 62 90 115 130 105 140 70 85 95 105 85 105 69,600 69,600
69,600 69,600 69,600 69,600 3004-H32 -H34 -H36 -H38 -H34 -H36 Sheet
& Plate Sheet & Plate Sheet Sheet Drawn Tube Drawn Tube
0.40 to 50.00 0.20 to 25.00 0.15 to 4.00 0.15 to 3.20 0.45 to 11.50
0.45 to 11.50 190 220 240 260 220 240 145 170 190 215 170 190 125
150 170 200 165 185 115 130 140 145 130 140 69,600 69,600 69,600
69,600 69,600 69,600 Alclad 3004-H32 -H34 -H36 -H38 -H131, H241,
H341 -H151, H261, H361 Sheet Sheet Sheet Sheet Sheet Sheet 0.40 to
6.30 0.20 to 6.30 0.15 to 4.00 0.15 to 3.20 0.60 to 1.20 0.60 to
1.20 185 215 235 255 215 235 140 165 185 205 180 205 115 145 165
195 150 195 110 125 130 145 125 130 69,600 69,600 69,600 69,600
69,600 69,600 3005-H25 -H28 Sheet Sheet 0.32 to 1.20 0.15 to 2.00
180 215 150 185 140 170 105 115 69,600 69,600 3105-H25 Sheet 0.32
to 2.00 160 130 115 95 69,600 5005-H12 -H14 -H16 -H32 -H34 -H36
Sheet & Plate Sheet & Plate Sheet Sheet & Plate Sheet
& Plate Sheet 0.40 to 50.00 0.20 to 25.00 0.15 to 4.00 0.40 to
50.00 0.20 to 25.00 0.15 to 4.00 125 145 165 120 140 160 95 115 135
85 105 125 90 105 125 75 95 110 75 85 95 75 85 90 69,600 69,600
69,600 69,600 69,600 69,600 5050-H32 -H34 -H32 -H34 Sheet Sheet
Cold Fin. Rod & Bar Drawn Tube Cold Fin. Rod & Bar Drawn
Tube 0.40 to 6.30 0.20 to 6.30 All All 150 170 150 170 110 140 110
140 95 125 105 130 95 105 90 105 69,600 69,600 69,600 69,600 For
all footnotes, see last page of this Table. ( )
24. I-A-18 January 2005 Table 3.3-1M MINIMUM MECHANICAL
PROPERTIES FOR ALUMINUM ALLOYS ALLOY AND TEMPER PRODUCT THICKNESS
RANGE mm Ftu MPa Fty MPa Fcy MPa Fsu MPa COMPRESSIVE MODULUS OF
ELASTICITY2 E (MPa) 5052-O -H32 -H34 -H36 Sheet & Plate Sheet
& Plate Cold Fin. Rod & Bar Drawn Tube Sheet 0.15 to 80.00
All All 0.15 to 4.00 170 215 235 255 65 160 180 200 66 145 165 180
110 130 140 150 70,300 70,300 70,300 70,300 5083-O -H111 -H111 -O
-H116 -H32, H321 -H116 -H32, H321 Extrusions Extrusions Extrusions
Sheet & Plate Sheet & Plate Sheet & Plate Plate Plate
up thru 13.00 up thru 12.70 12.70 to 130.00 1.20 to 6.30 4.00 to
40.00 4.00 to 40.00 40.00 to 80.00 40.00 to 80.00 270 275 275 275
305 305 285 285 110 165 165 125 215 215 200 200 110 145 145 125 180
180 165 165 165 165 160 170 180 180 165 165 71,700 71,700 71,700
71,700 71,700 71,700 71,700 71,700 5086-O -H111 -H111 -O -H112
-H112 -H112 -H116 -H32 -H34 Extrusions Extrusions Extrusions Sheet
& Plate Sheet & Plate Plate Plate Sheet & Plate Sheet
& Plate Drawn Tube Sheet & Plate Drawn Tube up thru 130.00
up thru 12.70 12.70 to 130.00 0.50 to 50.00 4.00 to 12.50 12.50 to
40.00 40.00 to 80.00 1.60 to 50.00 All All 240 250 250 240 250 240
235 275 275 300 95 145 145 95 125 105 95 195 195 235 95 125 125 95
115 110 105 180 180 220 145 145 145 145 150 145 145 165 165 180
71,700 71,700 71,700 71,700 71,700 71,700 71,700 71,700 71,700
71,700 5154-H38 Sheet 0.15 to 3.20 310 240 230 165 71,700 5454-O
-H111 -H111 -H112 -O -H32 -H34 Extrusions Extrusions Extrusions
Extrusions Sheet & Plate Sheet & Plate Sheet & Plate up
thru 130.00 up thru 12.70 12.70 to 130.00 up thru 130.00 0.50 to
80.00 0.50 to 50.00 0.50 to 25.00 215 230 230 215 215 250 270 85
130 130 85 85 180 200 85 110 110 90 85 165 185 130 140 130 130 130
145 160 71,700 71,700 71,700 71,700 71,700 71,700 71,700 5456-O
-H116 -H32, H321 -H116 -H32, H321 -H116 -H32, H321 Sheet &
Plate Sheet & Plate Sheet & Plate Plate Plate Plate Plate
1.20 to 6.30 4.00 to 12.50 4.00 to 12.50 12.50 to 40.00 12.50 to
40.00 40.00 to 80.00 40.00 to 80.00 290 315 315 305 305 285 285 130
230 230 215 215 200 200 130 185 185 170 170 170 170 180 185 185 170
170 170 170 71,700 71,700 71,700 71,700 71,700 71,700 71,700
6005-T5 Extrusions up thru 25 260 240 240 165 69,600 6061-T6, T651
-T6, T6510, T6511 -T6, T651 -T6 -T6 Sheet & Plate Extrusions
Cold Fin. Rod & Bar Drawn Tube Pipe 0.25 to 100.00 All up thru
200 0.63 to 12.50 All 290 260 290 290 260 240 240 240 240 240 240
240 240 240 240 185 165 170 185 165 69,600 69,600 69,600 69,600
69,600 6063-T5, -T52 -T5 -T6 Extrusions Extrusions Extrusions
Extrusions & Pipe up thru 12.50 up thru 25.00 12.50 to 25.00
All 150 150 145 205 110 110 105 170 110 110 105 170 90 90 85 130
69,600 69,600 69,600 69,600 6066-T6, T6510, T6511 Extrusions All
345 310 310 185 69,600 6070-T6, T62 Extrusions up thru 80.00 330
310 310 200 69,600 6105-T5 Extrusions up thru 12.50 260 240 240 165
69,600 6351-T5 Extrusions up thru 25.00 260 240 240 165 69,600
6351-T6 Extrusions up thru 20.00 290 255 255 185 69,600 6463-T6
Extrusions up thru 12.50 205 170 170 130 69,600 7005-T53 Extrusions
up thru 20.00 345 305 295 195 72,400 1. Ftu and Fty are minimum
specied values (except Fty for 1100-H12, H14 Cold Finished Rod and
Bar and Drawn Tube, Alclad 3003-H18 Sheet and 5050-H32, H34 Cold
Finished Rod and Bar which are minimum expected values); other
strength properties are corresponding minimum expected values. 2.
Typical values. For deection calculations an average modulus of
elasticity is used; this is 700 MPa lower than values in this
column. ( )
25. January 2005 I-A-19 Table 3.3-2 MINIMUM MECHANICAL
PROPERTIES FOR WELDED ALUMINUM ALLOYS ALLOY AND TEMPER PRODUCT
THICKNESS RANGE in. TENSION COMPRESSION Fcyw 2 ksi SHEAR Fsuw ksi
Ftuw 1 ksi Ftyw 2 ksi 1100-H12, H14 All 11 3.5 3.5 8 3003-H12, H14,
H16, H18 All 14 5 5 10 Alclad 3003-H12, H14, H16, H18 All 13 4.5
4.5 10 3004-H32, H34, H36, H38 All 22 8.5 8.5 14 Alclad 3004-H32,
H34, H36, H38 All 21 8 8 13 3005-H25 Sheet 17 6.5 6.5 12 5005-H12,
H14, H32, H34 All 15 5 5 9 5050-H32, H34 All 18 6 6 12 5052-O, H32,
H34 All 25 9.5 9.5 16 5083- 5083- 5083- O, H111 O, H116, H32, H321
O, H116, H32, H321 Extrusions Sheet & Plate Plate 0.188-1.500
1.501-3.000 39 40 39 16 18 17 15 18 17 23 24 24 5086- 5086- 5086-
O, H111 H112 O, H32, H34, H116 Extrusions Plate Sheet & Plate
0.250-2.000 35 35 35 14 14 14 13 14 14 21 21 21 5154-H38 Sheet 30
11 11 19 5454- 5454- 5454- O, H111 H112 O, H32, H34 Extrusions
Extrusions Sheet & Plate 31 31 31 12 12 12 11 12 12 19 19 19
5456- 5456- O, H116, H32, H321 O, H116, H32, H321 Sheet & Plate
Plate 0.188-1.500 1.501-3.000 42 41 19 18 18 17 25 25 6005-T5
Extrusions up thru 0.250 24 13 13 15 6061- 6061- T6, T651, T6510,
T65113 T6, T651, T6510, T65114 All All over 0.375 24 24 15 11 15 11
15 15 6063-T5, T52, T6 All 17 8 8 11 6351- 6351- T5, T63 T5, T64
Extrusions Extrusions over 0.375 24 24 15 11 15 11 15 15 6463-T6
Extrusions 0.125-0.500 17 8 8 11 7005-T53 Extrusions up thru 0.750
40 24 24 22 1. Filler wires are listed in Table 7.1-1. Values of
Ftuw are AWS D1.2 weld qualication values. 2. 0.2% offset in 2 in.
gage length across a groove weld. 3. Values when welded with 5183,
5356, or 5556 alloy ller wire, regardless of thickness. Values also
apply to thicknesses less than or equal to 0.375 in. when welded
with 4043, 5554, or 5654 alloy ller wire. 4. Values when welded
with 4043, 5554, or 5654 alloy ller wire.
26. I-A-20 January 2005 Table 3.3-2M MINIMUM MECHANICAL
PROPERTIES FOR WELDED ALUMINUM ALLOYS ALLOY AND TEMPER PRODUCT
THICKNESS RANGE mm TENSION COMPRESSION Fcyw 2 MPa SHEAR Fsuw MPa
Ftuw 1 MPa Ftyw 2 MPa 1100-H12, H14 All 75 25 25 55 3003-H12, H14,
H16, H18 All 95 35 35 70 Alclad 3003-H12, H14, H16, H18 All 90 30
30 70 3004-H32, H34, H36, H38 All 150 60 60 95 Alclad 3004-H32,
H34, H36, H38 All 145 55 55 90 3005-H25 Sheet 115 45 45 85
5005-H12, H14, H32, H34 All 105 35 35 62 5050-H32, H34 All 125 40
40 85 5052-O, H32, H34 All 170 65 65 110 5083- 5083- 5083- O, H111
O, H116, H32, H321 O, H116, H32, H321 Extrusions Sheet & Plate
Plate 6.30-38.00 38.00-80.00 270 270 270 110 115 115 110 115 115
160 165 165 5086- 5086- 5086- O, H111 H112 O, H32, H34, H116
Extrusions Plate Sheet & Plate 6.30-50.00 240 240 240 95 95 95
85 95 95 145 145 145 5154-H38 Sheet 205 75 75 130 5454- 5454- 5454-
O, H111 H112 O, H32, H34 Extrusions Extrusions Sheet & Plate
215 215 215 85 85 85 85 85 85 130 130 130 5456- 5456- O, H116, H32,
H321 O, H116, H32, H321 Sheet & Plate Plate 6.30-38.00
38.00-80.00 285 285 125 125 125 120 170 170 6005-T5 Extrusions up
thru 12.50 165 90 90 105 6061- 6061- T6, T651, T6510, T65113 T6,
T651, T6510, T65114 All All over 9.50 165 165 105 80 105 80 105 105
6063-T5, T52, T6 All 115 55 55 75 6351- 6351- T5, T63 T5, T64
Extrusions Extrusions over 9.50 165 165 105 80 105 80 105 105
6463-T6 Extrusions 3.20-12.50 115 55 55 75 7005-T53 Extrusions up
thru 20.00 275 165 165 155 1. Filler wires are listed in Table
7.1-1. Values of Ftuw are AWS D1.2 weld qualication values. 2. 0.2%
offset in 50 mm gage length across a groove weld. 3. Values when
welded with 5183, 5356, or 5556 alloy ller wire, regardless of
thickness. Values also apply to thicknesses less than or equal to
9.5 mm when welded with 4043, 5554, or 5654 alloy ller wire. 4.
Values when welded with 4043, 5554, or 5654 alloy ller wire.
27. January 2005 I-A-21 Table 3.3-3 FORMULAS FOR BUCKLING
CONSTANTS FOR PRODUCTS WHOSE TEMPER DESIGNATION BEGINS WITH -O, -H,
-T1, -T2, -T3, OR -T4 Type of Member and Stress Intercept ksi
Intercept MPa Slope Intersection Compression in Columns and Beam
Flanges Bc = Fcy [1 + ( Fcy_____ 1000) 1/2 ] Bc = Fcy [1 + (
Fcy_____ 6900) 1/2 ] Dc = Bc___ 20 (6Bc___ E ) 1/2 Cc = 2Bc____ 3Dc
Axial Compression in Flat Elements Bp = Fcy [1 + (Fcy )1/3 ______
7.6 ] Bp = Fcy [1 + (Fcy )1/3 ______ 14.5 ] Dp = Bp___ 20 (6Bp___ E
)1/2 Cp = 2Bp____ 3Dp Axial Compression in Curved Elements Bt = Fcy
[1 + (Fcy )1/5 ______ 5.8 ] Bt = Fcy [1 + (Fcy )1/5 ______ 8.5 ] Dt
= Bt___ 3.7 (Bt__ E ) 1/3 Ct* Bending Compression in Flat Elements
Bbr = 1.3Fcy [1 + (Fcy )1/3 ______ 7 ] Bbr = 1.3Fcy [1 + (Fcy )1/3
_____ 13.3 ] Dbr = Bbr___ 20 (6Bbr____ E ) 1/2 Cbr = 2Bbr____ 3Dbr
Bending Compression in Curved Elements Btb = 1.5Fy [1 + (Fy )1/5
______ 5.8 ] Btb = 1.5Fy [1 + (Fy )1/5 _____ 8.5 ] Dtb = Btb___ 2.7
(Btb___ E ) 1/3 Ctb =(Btb Bt_______ Dtb Dt ) 2 Shear in Flat
Elements Bs = Fty___ __ 3 [1 + (Fty / __ 3 )1/3 _________ 6.2 ] Bs
= Fty___ __ 3 [1 + (Fty / __ 3 )1/3 _________ 11.8 ] Ds = Bs___ 20
(6Bs___ E ) 1/2 Cs = 2Bs____ 3Ds Ultimate Strength of Flat Elements
in Compression or Bending k1 = 0.50, k2 = 2.04 *Ct shall be
determined using a plot of curves of limit state stress based on
elastic and inelastic buckling or by trial and error solution.
28. I-A-22 January 2005 Table 3.3-4 FORMULAS FOR BUCKLING
CONSTANTS FOR PRODUCTS WHOSE TEMPER DESIGNATION BEGINS WITH -T5,
-T6, -T7, -T8, OR -T9 Type of Member and Stress Intercept ksi
Intercept MPa Slope Intersection Compression in Columns and Beam
Flanges Bc = Fcy [1 + ( Fcy_____ 2250) 1/2 ] Bc = Fcy [1 + (
Fcy______ 15510) 1/2 ] Dc = Bc___ 10 (Bc__ E ) 1/2 Cc = 0.41 Bc___
Dc Axial Compression in Flat Elements Bp = Fcy [1 + (Fcy )1/3
______ 11.4 ] Bp = Fcy [1 + (Fcy )1/3 ______ 21.7 ] Dp = Bp___ 10
(Bp__ E ) 1/2 Cp = 0.41 Bp___ Dp Axial Compression in Curved
Elements Bt = Fcy [1 + (Fcy )1/5 ______ 8.7 ] Bt = Fcy [1 + (Fcy
)1/5 ______ 12.8 ] Dt = Bt___ 4.5 (Bt__ E ) 1/3 Ct* Bending
Compression in Flat Elements Bbr = 1.3Fcy [1 + (Fcy )1/3 _____ 7 ]
Bbr = 1.3Fcy [1 + (Fcy )1/3 _____ 13.3 ] Dbr = Bbr___ 20 (6Bbr____
E ) 1/2 Cbr = 2Bbr____ 3Dbr Bending Compression in Curved Elements
Btb = 1.5Fy [1 + (Fy )1/5 _____ 8.7 ] Btb = 1.5Fy [1 + (Fy )1/5
_____ 12.8 ] Dtb = Btb___ 2.7 (Btb___ E ) 1/3 Ctb = (Btb Bt_______
Dtb Dt ) 2 Shear in Flat Elements Bs = Fty___ __ 3 [1 + (Fty / __ 3
)1/3 _________ 9.3 ] Bs = Fty___ __ 3 [1 + (Fty / __ 3 )1/3
_________ 17.7 ] Ds = Bs___ 10 (Bs__ E ) 1/2 Cs = 0.41 Bs___ Ds
Ultimate Strength of Flat Elements in Compression k1 = 0.35, k2 =
2.27 Ultimate Strength of Flat Elements in Bending k1 = 0.50, k2 =
2.04 *Ct shall be determined using a plot of curves of limit state
stress based on elastic and inelastic buckling or by trial and
error solution.
29. January 2005 I-A-23 3.4 Allowable Stresses Allowable
stresses shall be determined in accordance with provisions of this
Specication. In the following subsections: The factors nu, ny, and
na shall be taken from Table 3.4-1. Values of coefcient kt shall be
taken from Table 3.4-2. Table 3.4-1 SAFETY FACTORS Building and
similar type structures Bridge and similar type structures nu 1.95
2.20 ny 1.65 1.85 na 1.20 1.35 Other safety factors are given
throughout this Specification. Table 3.4-2 COEFFICIENT kt Alloy and
Temper Non-welded or Regions Farther than 1.0 in. (25 mm) from a
Weld Regions Within 1.0 in. (25 mm) of a Weld 2014-T6, -T651,
-T6510, -T6511 Alclad 2014-T6, -T651 1.25 6066-T6, -T6510, -T6511
1.1 6070-T6, -T62 1.1 All Others Listed in Table 3.3-1 1.0 1.0 kt
is used in Sections 3.4.1, 3.4.2, 3.4.3, and 3.4.4. Values of k1
and k2 shall be taken from Tables 3.3-3 and 3.3-4. The formulas of
this Section are also listed in Table 3.4-3.
31. January 2005 I-A-25 TypeofStressTypeofMemberorElement Sub-
Sec. Allowable Stress SlendernessS1 Slenderness LimitS1
AllowableStress S1
32. I-A-26 January 2005 3.4.1 Tension, Axial Axial tensile
stress shall not exceed F = Fty/ny (Eq. 3.4.1-1) on the gross area
and F = Ftu/(kt )(nu ) (Eq. 3.4.1-2) on the effective net area (see
Section 5.1.5). Values of nu and ny are listed in Table 3.4-1.
Values of kt are listed in Table 3.4-2. Block shear rupture
strength provisions for the end con- nections of tension members
are given in Section 5.1.3. 3.4.2 Tension in Extreme Fibers of
Beams Flat Elements In Uniform Tension The allowable stress is the
lesser of: F = Fty___ ny and F = Ftu___ ktnu 3.4.3 Tension in
Extreme Fibers of Beams Round or Oval Tubes The allowable stress is
the lesser of: F = 1.17Fty______ ny (Eq. 3.4.3-1) and F =
1.24Ftu______ kt nu (Eq. 3.4.3-2) 3.4.4 Tension in Extreme Fibers
of Beams Flat Elements In Bending in Their Own Plane a. For
elements symmetric about the bending axis, the allowable stress is
the lesser of: F = 1.3Fty_____ ny (Eq. 3.4.4-1) and F =
1.42Ftu______ kt nu (Eq. 3.4.4-2) b. For elements unsymmetric about
the bending axis, the extreme ber stress of the element shall not
exceed the limiting value from a. and the stress at midheight of
the element shall not exceed the stress given in Sec- tion 3.4.2.
3.4.5 Bearing on Rivets and Bolts F = 2Ftu /nu (Eq. 3.4.5-1) This
value shall be used for a ratio of edge distance to fas- tener
diameter of 2 or greater. For smaller ratios this allow- able
stress shall be multiplied by the ratio: (edge distance)/ (2
fastener diameter). Edge distance is the distance from the center
of the fastener to the edge of the material in the direction of the
applied load and shall not be less than 1.5 times the fastener
diameter to extruded, sheared, sawed, rolled, or planed edges.
3.4.6 Bearing on Flat Surfaces and Pins and on Bolts in Slotted
Holes F = 2Ftu /(1.5nu ) (Eq. 3.4.6-1) (See Section 5.2.2 for
limits on slot lengths.) 3.4.7 Compression in Columns, Axial, Gross
Section For members in axial compression, the allowable stress is
the lesser of that determined from this Section and Sec- tions
3.4.8 through 3.4.10. a. Fc = Fcy___ ny (Eq. 3.4.7-1) for kL___ r
S1 b. Fc = (Bc Dc kL_____ r )__________ nu (Eq. 3.4.7-2) for S1
< kL___ r < S2 c. Fc = 2 E_______ nu (kL___ r )2 (Eq.
3.4.7-3) for kL___ r S2 where S1 = Bc nuFcy_____ ny________ Dc (Eq.
3.4.7-4) S2 = Cc (Eq. 3.4.7-5) k = the effective length factor by
rational analysis. k shall be taken larger than or equal to unity
unless rational analysis justies a smaller value. L = the
unsupported length r = radius of gyration of the column about the
axis of buckling 3.4.7.1 Sections Not Subject to Torsional or
Torsional-Flexural Buckling For closed sections and other sections
that are not sub- ject to torsional or torsional-exural buckling,
kL___ r shall be the largest slenderness ratio for exural buckling
of the column. 3.4.7.2 Doubly or Singly Symmetric Sections Subject
to Torsional or Torsional- Flexural Buckling For doubly or singly
symmetric sections subject to tor- sional or torsional-exural
buckling kL___ r shall be the larger of the largest slenderness
ratio for exural buckling and the equivalent slenderness ratio
determined for torsional-exural buckling as follows:
33. January 2005 I-A-27 (kL___ r )e = ___ E__ Fe (Eq.
3.4.7.2-1) where Fe is the elastic critical stress determined as
follows: For torsional buckling: Fe = Fet (Eq. 3.4.7.2-2) For
torsional-exural buckling: Fe = Fef = 1___ 2 [(Fex + Fet )
__________________ (Fex + Fet )2 4FexFet ] (Eq. 3.4.7.2-3)
Alternatively, for torsional-exural buckling, a conservative
estimate of Fe shall be permitted to be obtained as follows: Fe =
Fef = FexFet_______ Fex + Fet (Eq. 3.4.7.2-4) In the above
equations x-axis is the centroidal symmetry axis A =
cross-sectional area Cw = torsional warping constant of the
cross-section E = compressive modulus of elasticity (See Table
3.3-1) Fex = 2 E______ (kxLb____ rx )2 (Eq. 3.4.7.2-5) Fet = 1____
Ar 2 O (GJ + 2 ECw______ (KtLt)2 ) (Eq. 3.4.7.2-6) G = shear
modulus = 3E/8 (Eq. 3.4.7.2-7) J = torsion constant kx = effective
length coefcient for buckling about the x-axis Kt = effective
length coefcient for torsional buckling. Kt shall be taken larger
than or equal to unity unless rational analysis justies a smaller
value. Lt = unbraced length for twisting Lb = unbraced length for
bending about the x-axis ro = ___________ r 2 x + r 2 y + x 2 o
(Eq. 3.4.7.2-8) polar radius of gyration of the cross-section about
the shear center. rx, ry = radii of gyration of the cross-section
about the centroidal principal axes xo = x - coordinate of the
shear center = 1 (xo /ro )2 (Eq. 3.4.7.2-9) 3.4.7.3 Nonsymmetric
Sections Subject to Torsional or Torsional-Flexural Buckling For
nonsymmetric sections subject to torsional or torsional-exural
buckling kL___ r shall be determined by rational analysis. 3.4.8
Uniform Compression in Elements of Columns Whose Buckling Axis is
an Axis of SymmetryFlat Elements Supported On One Edge a. Fc =
Fcy___ ny (Eq. 3.4.8-1) for b/t S1 b. Fc = 1__ nu [Bp 5.1Dp b__ t ]
(Eq. 3.4.8-2) for S1 < b/t < S2 c. Fc = k2 ____ BpE________
nu(5.1b/t) (Eq. 3.4.8-3) for b/t S2 where S1 = Bp nu__ ny Fcy
_________ 5.1Dp (Eq. 3.4.8-4) S2 = k1Bp_____ 5.1Dp (Eq. 3.4.8-5) b
= distance from unsupported edge of element to toe of the llet or
bend, except if the inside corner radius exceeds 4 times the
thickness; then the inside radius shall be assumed equal to 4 times
the thickness in calculating b. Element width b is illustrated in
Figure 3.4.8-1. 3.4.8.1 Uniform Compression in Elements of Columns
Whose Buckling Axis is not an Axis of SymmetryFlat Elements
Supported On One Edge a. Fc = Fcy___ ny (Eq. 3.4.8.1-1) for b/t S1
b. Fc = 1__ nu [Bp 5.1Dp b__ t ] (Eq. 3.4.8.1-2) for S1 < b/t
< S2 c. Fc = 2 E_________ nu(5.1b/t)2 (Eq. 3.4.8.1-3) for b/t S2
where S1 = Bp nu__ ny Fcy _________ 5.1Dp (Eq. 3.4.8.1-4) S2 =
Cp___ 5.1 (Eq. 3.4.8.1-5) b = distance from unsupported edge of
element to toe of the llet or bend, except if the inside corner
radius exceeds 4 times the thickness; then the inside radius shall
be assumed equal to 4 times the thickness in calculating b. Element
width b is illustrated in Figure 3.4.8-1.
34. I-A-28 January 2005 3.4.9 Uniform Compression in Elements
of ColumnsFlat Elements Supported on Both Edges a. Fc = Fcy___ ny
(Eq. 3.4.9-1) for b/t S1 b. Fc = 1__ nu [Bp 1.6Dp b__ t ] (Eq.
3.4.9-2) for S1 < b/t < S2 c. Fc = k2 ____ BpE________
nu(1.6b/t) (Eq. 3.4.9-3) for b/t S2 where S1 = Bp nu__ ny Fcy
_________ 1.6Dp (Eq. 3.4.9-4) S2 = k1Bp_____ 1.6Dp (Eq. 3.4.9-5) b
= distance from unsupported edge of element to toe of the llet or
bend, except if the inside corner radius exceeds 4 times the
thickness; then the inside radius shall be assumed equal to 4 times
the thickness in calculating b. Element width b is illustrated in
Figure 3.4.9-1. 3.4.9.1 Uniform Compression in Elements of
ColumnsFlat Elements Supported on One Edge and With Stiffener on
Other Edge The provisions of this Section apply when Ds /b 0.8. The
allowable stress is the lesser of Fc = Fcy___ ny (Eq. 3.4.9.1-1)
and Fc = FUT + (FST FUT )ST FST (Eq. 3.4.9.1-2) Figure 3.4.8-1 FLAT
ELEMENTS SUPPORTED ON ONE EDGE If r > 4t, then use r = 4t to
calculate b.
35. January 2005 I-A-29 For a simple straight lip edge
stiffener of constant thick- ness, Fc shall not exceed the
allowable stress for the stiffener according to Section 3.4.8. In
the above equations Ds = dened in Figure 3.4.9.1-1 and -2 FUT =
allowable stress according to Section 3.4.8 neglecting the
stiffener FST = allowable stress according to Section 3.4.9 ST =
ratio to be determined as follows: ST = 1.0 for b/t S/3 (Eq.
3.4.9.1-3) ST = rs_________ 9t(b/t___ S 1__ 3) 1.0 for S/3 < b/t
S (Eq. 3.4.9.1-4) ST = rs___________ 1.5t (b/t___ S + 3) 1.0 for 2S
> b/t > S (Eq. 3.4.9.1-5) rs = radius of gyration of the
stiffener determined as follows: - For simple straight lip
stiffeners of con- stant thickness similar to that shown in Figure
3.4.9.1-1, rs shall be calculated as: rs = ds sin ______ __ 3 - for
other stiffeners, rs shall be calculated about the mid-thickness of
the element being stiffened ds = at width of lip stiffener shown in
Figure 3.4.9.1-1 S = 1.28 ___ E___ Fcy b = distance from
unsupported edge of element to toe of llet or bend, except if the
inside corner radius exceeds 4 times the thickness; then the inside
radius shall be assumed to equal 4 times the thickness in
calculating b. Element width b is illustrated in Figures 3.4.9.1-1.
and 3.4.9.1-2 Figure 3.4.9-1 FLAT ELEMENTS SUPPORTED ON BOTH EDGES
If r > 4t, then use r = 4t to calculate b.
36. I-A-30 January 2005 3.4.9.2 Uniform Compression in Elements
of ColumnsFlat Elements Supported on Both Edges and With an
Intermediate Stiffener a. Fc = Fcy___ ny (Eq. 3.4.9.2-1) for s S1
b. Fc = (Bc Dcs)_________ nu (Eq. 3.4.9.2-2) for S1 < s < S2
c. Fc = 2 E____ nus 2 (Eq. 3.4.9.2-3) for s S2 The allowable stress
Fc obtained above shall not be more than the allowable stress
according to Section 3.4.9 for the sub-elements of the
intermediately stiffened element. The allowable stress Fc obtained
above shall not be less than that determined according to Section
3.4.9 ignoring the intermediate stiffener. Figure 3.4.9.1-1 EDGE
STIFFENED ELEMENTS If r > 4t, then use r = 4t to calculate b.
Figure 3.4.9.1-2 EDGE STIFFENED ELEMENTS If r > 4t, then use r =
4t to calculate b.
37. January 2005 I-A-31 In the above equations: As = area of
the stiffener Io = moment of inertia of a section comprising the
stiff- ener and one half of the width of the adjacent sub- elements
and the transition corners between them taken about the centroidal
axis of the section parallel to the element that is stiffened
(Figure 3.4.9.2-1). S1 = Bc nuFcy_____ ny_____ Dc (Eq. 3.4.9.2-4)
S2 = Cc (Eq. 3.4.9.2-5) s = 4.62(b__ t ) _______________ 1 + As /
bt_______________ 1 + __________ 1 + 10.67Io_______ bt3 (Eq.
3.4.9.2-6) Figure 3.4.9.2-1 FLAT ELEMENTS WITH AN INTERMEDIATE
STIFFENER Line o-o is the neutral axis of the stiffener and plate
of width b/2 on each side of the stiffener. Io is the moment of
inertia of the portion shown in the partial section. If r > 4t,
then use r = 4t to calculate b.
38. I-A-32 March 2006 3.4.10 Uniform Compression in Elements of
ColumnsCurved Elements Supported on Both Edges a. Fc = Fcy___ ny
(Eq. 3.4.10-1) for Rb/t S1 b. Fc = 1__ nu [Bt Dt ___ Rb__ t ] (Eq.
3.4.10-2) for S1 < Rb/t < S2 c. Fc = 2 E__________________
16nu (Rb__ t )(1 + ____ Rb /t_____ 35 ) 2 (Eq. 3.4.10-3) for Rb/t
S2 where S1 = (Bt nu__ ny Fcy ________ Dt ) 2 (Eq. 3.4.10-4) S2 =
Ct (Eq. 3.4.10-5) For tubes with circumferential welds, the
equations of this Section apply for Rb/t 20. 3.4.11 Compression in
Beams, Extreme Fiber, Gross SectionSingle Web Shapes For single web
shapes not subject to lateral buckling (bent about the strong axis
with continuous lateral support or bent about the weak axis),
determine the compressive allowable stress Fc from Sections 3.4.15
through 3.4.19 as applicable. For single web shapes subject to
lateral buckling (bent about the strong axis without continuous
lateral support), the compressive allowable stress Fc is the lesser
of that determined from Sections 3.4.15 through 3.4.19 as appli-
cable and the following: a. Fc = Fcy___ ny (Eq. 3.4.11-1) for
Lb_____ ry ___ Cb S1 b. Fc = (Bc DcLb________ 1.2ry ___ Cb
)____________ ny (Eq. 3.4.11-2) for S1 < Lb_____ ry ___ Cb <
S2 c. Fc = Cb2 E________ ny ( Lb____ 1.2ry ) 2 (Eq. 3.4.11-3) for
Lb_____ ry ___ Cb S2 where S1 = 1.2 (Bc Fcy )___________ Dc (Eq.
3.4.11-4) S2 = 1.2Cc (Eq. 3.4.11-5) ry = radius of gyration of the
shape (about an axis parallel to the web) (For beams that are
unsym- metrical about the horizontal axis, ry shall be calculated
as though both anges were the same as the compression ange). Lb =
length of the beam between bracing points or between a brace point
and the free end of a cantilever beam. Bracing points are the
points at which the compression ange is restrained against lateral
movement or the cross section is restrained against twisting. Cb =
coefcient that depends on moment variation over the unbraced
length. Cb shall be as given in Section 4.9.4 or taken as 1.
Alternatively, Fc may be calculated by replacing ry by rye given in
Section 4.9. 3.4.12 Compression in Beams, Extreme Fiber, Gross
SectionRound or Oval Tubes a. Fc = 1.17Fcy______ ny (Eq. 3.4.12-1)
for Rb/t S1 b. Fc = 1__ ny (Btb Dtb ___ Rb__ t ) (Eq. 3.4.12-2) for
S1 < Rb/t < S2 c. For Rb/t S2, the allowable bending stress
shall be determined from the formulas for tubes in compres- sion in
Section 3.4.10 using the formula that is appro- priate for the
particular value of Rb /t. In the above equations Rb =
mid-thickness radius of a round element or max- imum mid-thickness
radius of an oval element S1 = (Btb 1.17Fcy__________ Dtb ) 2 (Eq.
3.4.12-3) S2 = ( nu__ ny Btb Bt _________ nu__ ny Dtb Dt ) 2 (Eq.
3.4.12-4) For tubes with circumferential welds, the equations of
this Section apply for Rb/t 20. 3.4.13 Compression in Beams,
Extreme Fiber, Gross SectionSolid Rectangular and Round Sections
For rectangular sections bent about the weak axis, rod, and square
bar: Fc = 1.3Fcy_____ ny For rectangular sections bent about the
strong axis: a. Fc = 1.3Fcy_____ ny (Eq. 3.4.13-1) for d__ t ____
Lb____ Cb d S1
39. January 2005 I-A-33 b. Fc = 1__ ny (Bbr 2.3Dbr d__ t ____
Lb____ Cbd ) (Eq. 3.4.13-2) for S1 < d__ t ____ Lb____ Cbd <
S2 c. Fc = 2 E___