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					1)   Table 2002.4 FBC is predicated upon 20/20 screen (0.013" Ø wire), if an
     allowance is made for screen less dense (18/14), the appropriate pressures
     are indicated on the Table page.
2)   Allowable stresses and moments (member bending capacities) have been
     calculated using the 2005 Aluminum Design Manual as is required by
     Chapter 20 FBC. Values varying from these of more than a reasonable range
     are not code compliant.
3)   Beam Moment Calculator worksheet has been protected so that users cannot
     change the contents of any cell except for the yellow background cells
     (send me an email if you want to change any of the other cells)
4)   The calculation works for most common beam shapes (flat, mansard, gable).
5)   Dimensional entries are in decimal feet, use the diagram to the right for guidance.
6)   Calculator "suggested members" do not consider simultaneous axial beam or post
     compression and thus is not conservative, it only calculates bending moment and
     compares the result to the tables on the "Allowables" worksheet and selects
     members accordingly. However the component selectors at C36 consider
     bending and axial compression as shown.
7)   6061T6 alloy is structurally equivalent to 6005T5
8)   a hinge or pin connection is assumed at the shoulder
9)   Comments, questions or criticisms should be directed to: forms@aaof.org

10) User instructions:
    a)     select wind zone (cell D6)
    b)     select wind exposure (cell G7)
    c)     if an allowance is to be made for screen density, select in D7
    d)     enter beam span in D9
    e)     enter screen eave height D10
    f)     enter rise (if beam is flat, enter zero) into cell D11
    g)     enter spacing of beams/posts into D12
    calculator will adjust accordingly and report findings
        Mansard, Gable or Horizontal Roof Beam & Post CALCULATOR
        (2D Calculator based upon Roof Up and Wall In for Beam Design
       Contractor Name: My company name                                     Date: 22-Nov-11
           Owner Name: My customer's name
           Site Address: Jobsite address
                            FOR WIND ZONE: 110          mph in Exposure Category:     B
                           SCREEN DENSITY: 18/14
                                                                              Design Pressures
                                  BEAM SPAN:   26.24 ft           Windward Wall:    11.4
                                  Eave Height: 10.33 ft             Leeward Wall:    7.9
                                         Rise:    3.5 ft                    Roof:    3.5
                          Beam/Post Spacing:    6.67 ft

                           Load on the column:      76.3   lbs/ft
                       Horizontal Load on Rise:     76.3   lbs/ft on Windward Side
                                    (Leeward):      52.8   lbs/ft on Leeward Side
 Wall pressure Horizontal Reaction at Shoulder:    394.1   lbs
Horizontal Reaction at Shoulder (Mansard Leg):     133.5   lbs
                (Horizontal) Reaction at Splice:   527.6   lbs (compression to plateau portion of beam)
                                Load on Beam:       23.5   lbs/ft

              Beam Moment 1 (uniform load):         24.2   in-kips
           Additional Moment (from shoulder):       16.6   in-kips      (eccentric load from shoulder)
 Additional Moment (Windward sloping beam):          5.6   in-kips
  Additional Moment (Leeward sloping beam):          3.9   in-kips
                                                                        Compression (lbs)
                  Total Beam Moment (Mmax):        50.3    in-kips            528

                     Column Bending Moment:        12.2    in-kips            308
                                                                        Members Suggested by Bending Only
                                                                           6063T6           6005T5
                                                                           2X8 SMB          2X8 SMB
                                                                           2X6 SMB          2X5 SMB

                          Members Selected                                 Deflection
                              6063T6               Displacements (in)        Ratio          fa factor
          User Select           2X6 SMB                       9.09           L / 35          27.7%
          User Select           2X4 SMB                       0.97          L / 128          18.3%
                                 6005T5                                                     fa factor
          User Select           2X9 SMB                       1.89          L / 166          8.7%
          User Select           2X5 SMB                       0.53          L / 233          11.9%
Deflections for Selected 6063T6 Members:
Convert beam moment to unit load on beam for deflection calculation:
                                         4.058 lbs/in (beam loading)
                  Span:                314.88 in
                  E:                   1E+07
                  I:                      5.66

                                          9.09 in
                     Defl Ratio = L/ 35

                 Post deflection:
                                      6.359 lbs/in (post loading)
                 Span:               123.96 in
                 E:                  1E+07
                 I:                       2
                                                       8
                                      0.97 in
                    Defl Ratio = L/ 128
                                                         Value   [YELLOW BACKROUND INDICATES A INPUT VALUES]
                                                         Value   [BLUE BACKROUND INDICATES A CALCULATED VALUE]




sign Pressures




portion of beam)




rom shoulder)




ested by Bending Only




                            Interaction
                               Ratio
                fb factor      Total
                346.80%     374.51%       OVERSTRESSED
                168.77%     187.10%       OVERSTRESSED
                fb factor     Total
                47.70%       56.40%         Design OK
                87.89%       99.81%         Design OK
Deflections for Selected 6005T6 or 6061T6 Members:
Convert beam moment to unit load on beam for deflection calculation:
                                      4.058 lbs/in (beam loading)
             Span:                   314.88 in
             E:                    10100000
             I:                       27.16

                                      1.89 in
        Defl Ratio = L/ 166

           Post deflection:
                                    6.359 lbs/in (post loading)
           Span:                   123.96 in
           E:                    10100000
           I:                       3.644

                                      0.53 in
        Defl Ratio = L/ 233
                                                       Screen Density Table   Exposures
TES A INPUT VALUES]                                                  20/20        B
 A CALCULATED VALUE]                                                 18/14        C
          LOOKUP TABLE, DO NOT DISTURB!!
          EXPOSURE CATEGORY:    B
          Design Pressures Table 2002.4
                        Wall Pressures
                    Windward Leeward         Roof
              100       12          10        3
              110       13          9         4
              120       15          13        4
              130       18          14        5
              140       21          15        6

          CrossRef Table        Index          ID
            2X4   SMB   S2X4            1    2X4 SMB
            2X5   SMB   S2X5            2    2X5 SMB
            2X6   SMB   S2X6            3    2X6 SMB
            2X7   SMB   S2X7            4    2X7 SMB
            2X8   SMB   S2X8            5    2X8 SMB
            2X9   SMB   S2X9            6    2X9 SMB
           2X10   SMB   S2X10           7   2X10 SMB
EXPOSURE B Design Pressures Table 2002.4   EXPOSURE C Design Pressures Table 2002.4
              Wall Pressures                            Wall Pressures
          Windward Leeward          Roof           Windward Leeward        Roof
   100        12          10          3       100     14.62       11.18     4.3
   110        13          9           4       110     15.48       12.04     4.3
   120        15          13          4       120     18.06       14.62    5.16
   130        18          14          5       130      21.5       16.34    6.02
   140        21          15          6       140     24.94       19.78    6.88
             20/20 Screen

    Table 2002.4 DESIGN WIND PRESSURES SCREENED ENCLOSUR
                          (EXPOSURE B)
                              Basic Wind Speed (mph)
                               Design Pressure (psf)
 Surface       100     110       120        130
Horizontal
Pressures
    on         12      13         15         18
Windward
 Surfaces

Horizontal
Pressures
    on         10      10         13         14
 Leeward
 Surfaces

 Vertical
Pressures
                3       4         4          5
on Screen
 Surfaces

 Vertical
Pressures
               10      11         13         15
 on Solid
Surfaces



             20/20 Screen
    Table 2002.4 DESIGN WIND PRESSURES SCREENED ENCLOSUR
              (EXPOSURE C for mean roof height = 15 ft)
                              Basic Wind Speed (mph)
                               Design Pressure (psf)
 Surface       100     110       120        130
Horizontal
Pressures
    on         14.6    15.5      18.1       21.5
Windward
 Surfaces
Horizontal
Pressures
    on       11.2   12.0   14.6   16.3
 Leeward
 Surfaces

 Vertical
Pressures
             4.3    4.3    5.2    6.0
on Screen
 Surfaces

 Vertical
Pressures
             12.0   12.9   15.5   18.1
 on Solid
Surfaces




Horizontal
Pressures
    on       17     18     21     25
Windward
 Surfaces

Horizontal
Pressures
    on       13     14     17     19
 Leeward
 Surfaces

 Vertical
Pressures
              5      5      6      7
on Screen
 Surfaces

 Vertical
Pressures
             14     15     18     21
 on Solid
Surfaces
                                          18/14 Screen

ES SCREENED ENCLOSURES           Table 2002.4 DESIGN WIND PRESSURES SCREENED ENCLOSUR
B)                                                     (EXPOSURE B)
Speed (mph)                                                Basic Wind Speed (mph)
essure (psf)                                                Design Pressure (psf)
               140    150     Surface       100     110       120        130
                             Horizontal
                             Pressures
               21     24         on         10.6    11.4      13.2       15.8
                             Windward
                              Surfaces

                             Horizontal
                             Pressures
               15     18         on         8.8     8.8       11.4       12.3
                              Leeward
                              Surfaces

                              Vertical
                             Pressures
                6      7                    2.6     3.5        3.5        4.4
                             on Screen
                              Surfaces

                              Vertical
                             Pressures
               17     20                    10      11         13         15
                              on Solid
                             Surfaces



                                          18/14 Screen
 ES SCREENED ENCLOSURES          Table 2002.4 DESIGN WIND PRESSURES SCREENED ENCLOSUR
of height = 15 ft)                         (EXPOSURE C for mean roof height = 15 ft)
Speed (mph)                                                Basic Wind Speed (mph)
essure (psf)                                                Design Pressure (psf)
               140    150     Surface       100     110       120        130
                             Horizontal
                             Pressures
               24.9   28.4       on         11.7    12.4      14.4       17.2
                             Windward
                              Surfaces
              Horizontal
              Pressures
19.8   23.2       on       8.9   9.6   11.7   13.1
               Leeward
               Surfaces

               Vertical
              Pressures
6.9    7.7                 3.4   3.4   4.1    4.8
              on Screen
               Surfaces

               Vertical
              Pressures
20.6   24.1                14    15    18     21
               on Solid
              Surfaces




29     33




23     27




 8      9




24     28
ES SCREENED ENCLOSURES
B)
Speed (mph)
essure (psf)
               140    150


               18.5   21.1




               13.2   15.8




               5.3    6.2




               17     20




 ES SCREENED ENCLOSURES
of height = 15 ft)
Speed (mph)
essure (psf)
               140    150


               20.0   22.7
15.8   18.6




5.5    6.2




24     28
Stainless Steel Cable (Ultimate Strength from: cmacable.com)
Commercial Cable Specifications
Cable Manufacturing and Assembly Co., Inc.


   Cable              Diameter
   Type          3/32"         1/8"
   1X19          1,200       2,100
    7X7           920        1,700
   7X19           920        1,760

Tensile Strength with 1.5 Factor of Safety
   Cable              Diameter
   Type          3/32"         1/8"
   1X19           800        1,400
    7X7           613        1,133
   7X19           613        1,173

Horizontally Applied Allowable Load at 45° Angle
   Cable             Diameter
   Type          3/32"        1/8"
   1X19           566           990
    7X7           434           801
   7X19           434           830
          This Calculation for Stitched SMB 6063T6 Sections

           Select Self-Mating Beam Section                           S2X6          SELECT member from dro

Weak axis (Y) un-braced Beam length (purlin spacing)        Enter:    96.000 in    Weak Axis Support Distance
Strong (X) axis support length (total unsupported length)   Enter:   314.880 in    Strong Axis Support Distance
Spacing of Flange Stitch Screws                             Enter:    24.000 in    Stich screw O.C. spacing


Self-Mating Profile Dimensions and Properties
Width b                                                               2.000 in
Height d                                                              6.000 in
Channel Flange Width bf used to calculate buckling                     1.510 in
Channel Flange Width bc                                                1.560 in
Web Height used for Buckling h = d - 2tf                               5.760 in
Flange Thickness tf                                                   0.120 in
Web thickness tw                                                      0.050 in
                                                                               2
Total Area (A)                                                         1.022 in
                                                                               2
Web Area ( Aw )                                                        0.576 in
                                                                               2
Flange Area (Af)                                                       0.480 in
                                                                               4
Torsional Constant (J)                                                 1.964 in
                                                                               4
Moment Of Inertia X-Axis Ix                                            5.660 in
                                                                               3
Section Modulus X-Axis Sx                                              1.944 in    Summary of Results for S
Radius of Gyration X-Axis rx                                           2.354 in     Member
                                                                               4
Moment Of Inertia Y-Axis Iy                                            0.685 in        S2X6
                                                                               3
Section Modulus Y-Axis Sy                                              0.685 in    [Allowable Stress values in ksi;
Radius of Gyration Y-Axis ry                                           0.819 in    Weight/ft of Section Conside

Open Channel properties - In weak axis
Channel Height dc                                                      5.940 in
Distance to the center of gravity from Outer Web Edge C1               0.321 in
To the other edge C2 - (bf -C1)                                        1.239 in
                                                                               4
Moment Inertia in weak axis Iyc                                        0.103 in
Radius of Gyration ryc                                                 0.464 in
                                                                               2
Cross section area                                                     0.478 in

               Allowable Major Axis Bending Moment

                         Tension
Tension 3.4.2 (Flat elements in Uniform Tension)            Fbtf     15.000
Tension 3.4.4 (Flat elements bending in their own plane)    Fbtw     20.000

                         Compression
Member Buckling 3.4.14
S = 2*Lb * Sx / SQRT( Iy * J) (Lb is Un-braced length)                 321.762
IF S <= 130 Then Fbcx = 15 ksi
IF S > 130 AND < 2400 Then Fbcx = (16.7 - 0.14) * S0.5
IF S >= 2400 Then Fbcx = 23,600/S
                                                Actual Fbcx            14.189 ksi
                Allowable Moment based upon 3.4.14                     27.583 kip-in

Member Buckling Between Stitch Screws 3.4.11
Lb - Stitch screw spacing
ryc - Minor axis radius of gyration
S= Lb / ryc                                                            51.723
IF S <= 22 Then Fbcxh = 15 ksi
IF S > 22 AND S < 94 Then Fbcxw = 16.7 - 0.073* S
IF S >= 94 Then Fcbxw = 87,000/S2
                                               Actual Fbcxh            12.924
                Allowable Moment based upon 3.4.11                     25.125 kip-in

Web Local Buckling 3.4.18
S=h/tw                                                                 115.200
IF S <= 53 Then Fbcxw = 20 ksi
IF S > 53 AND S < 90 Then Fbcxw = 27.9 - 0.155* S
IF S >= 90 Then Fcbxw = 1260/S
                                               Actual Fbcxw             10.938

Flange Local Buckling 3.4.15
S=2bf/tf                                                                25.167
IF S <= 7.2 Then Fbcxf = 15 ksi
IF S > 7.2 AND S < 12 Then Fbcxf = 19.0 - 0.541*S ksi
IF S >= 12 Then Fbcxf = 152/S ksi
                                                Actual Fcbxf             6.040

Maximum allowed bending stress Fbx (Section 3.4)                        6.040 ksi

Allowable Bending Moment per Section 4.7.3
                                                                                 4
Flange Group If = 2[(b*tf3 / 12) + b*tf*(d/2-tf/2)2]            If =     4.150 in
                                                                                 4
Web Group Moment of Inertia Iw = 2[(tw * (d-2*tf)3) /12]        Iw =     1.593 in
Dimension: Center of Compression Flange to Centroid            Ccf =     2.950 in
Dimension: Extreme Web Compression Fiber to Centroid           Ccw =     2.900 in
Dimension: Extreme Tension Fiber to Centroid                   Cif =     3.000 in
Dimension: Extreme Web Tension Fiber to Centroid               Ctw =     2.900 in
Allowable Compressive Bending Moment:                          Mac =    14.502 kip-in Mac = ((Fbcf*If)/Ccf)+((Fbcw*Iw
Allowable Tension Bending Moment:                              Mat =    31.730 kip-in Mat = ((Fbtf*If)/Ctf)+((Fbtw*Iw
Allowable Major Axis Moment based upon Beam Half Buckling        25.1    Kip-In
Average Allowable Bending Stress for 4.7.3 method:                7.5    ksi
Maximum Allowable Major Axis Moment (Section 3.4)                11.7    Kip-In
Maximum Allowable Major Axis Moment (Paragraph 4.7.3)            14.5    Kip-In Section 4.7.3 Governed by Fl
Maximum allowed Bending Moment (three methods)                   14.5    Kip-In Section 4.7.3 Governs


                          Axial Compression (Fc)

Member Buckling (ADM Specification 3.4.7)
Sx=kL/rx - k is assumed 1 worst case                           133.764
Sy=kL/ry - k is assumed 1 worst case                           117.216
S=kL/r (Larger of x or y axis)                                 133.764
[S=slenderness ratio]
If S < 78 then Fcm = 14.2 – 0.074 * S
If S >= 78 then Fcm = 51,100/S2
                                               Actual Fcm       2.856

Beam Half, Member Buckling between stitch screws (ADM 3.4.7)
k=0.5, L = Stitch spacing
ryc = Minor axis radius of gyration of section half
S = kL/ryc k = 0.5, L = 24.0 in                                 25.861
If S < 78 then Fch = 14.2 – 0.074 * S
If S >= 78 then Fch = 51,100/S2
                                               Actual Fch      12.286

Flange Local Buckling (ADM Specification 3.4.8.1)
S = 2*bf/tf                                                     25.167
if S <= 2.1 Then Fcf (ksi) = 15
if S > 2.1 AND < 14 Then Fcf (ksi) = 16.1 - 0.458 *S
if S >= 14 Then Fcf (ksi) = 1970/S2
                                                Actual Fcf      3.110

Web Local Buckling (ADM Specification 3.4.9)
S=h/tw                                                         115.200
If S <= 6.7 Then Fcw (ksi.) = 15
If S > 6.7 AND < 39 Then Fcw (ksi) = 16.1 - 0.144 * S
If S >= 39 Then Fcw (ksi) = 410/S
                                               Actual Fcw       3.559

Weighted Average Web / Flange Local Buckling (ADM 4.7.2)
Fca = (Fcw*Aw + Fcf*Af)/ A                                      3.467
Member Buckling Elastic (ADM 4.7.4)
Fec = π2E/(kL/r)2 ksi (Eq. 4.7.4-3)                                            5.571

Web Local Elastic Buckling (ADM Specification 4.7.1-1)
Fcrw (ksi) = π2*E/(1.6*S)2                                                     2.934

Flange Local Elastic Buckling (ADM Specification 3.4.8.1)
Fcrf = π2*E/(5.1*S)2                                                           6.051

Interaction Between Local and Member Buckling 4.7.4
The reduced member Buckling allowable stress
Frc = (Fec)1/3 * (Fcr)2/3 / nu.. nu = 1.95
Fec = Elastic member buckling                                                   2.856
Fcr = Minimum Elastic Local Buckling                                            2.934
nu = Structural factor of safety                                                1.950
IF Fcr /nu < Fec Then Frc = (Fec)1/3 * (Fcr)2/3 / nu                           1.863

Maximum allowable Axial compressive stress                                     1.863 ksi
Allowable Axial Compression                                                    1.904 k

                  Allowable Stress: Minor Axis Bending

Tension 3.4.4
Fbty                                                                           20.000 ksi

Web Local Buckling 3.4.16
S=h/tw                                                                        115.200
IF S <= 23 Then Fbcyw = 15 ksi
IF S > 23 AND S < 39 Then Fbcyw = 19.0 - 0.170* S
IF S >= 39 Then Fcbyw = 484/S
                                                   Actual Fbcyw                 4.201

Flange Local Buckling 3.4.17
S=2bf/tf                                                                       25.167
IF S <= 10 Then Fbcyf = 20 ksi
IF S > 10 AND S < 23 Then Fbcyf = 27.9 - 0.808*S ksi
IF S >= 23 Then Fbcyf = 4930/S2 ksi
                                                       Actual Fcbyf             7.784

Allowable Bending Moment per Section 4.7.3
                                                                                        4
Flange Group If = 2[(b*tf3 / 12) + b*tf*(d/2-tf/2)2]                   If =     0.490 in
                                                                                        4
Web Group Moment of Inertia Iw = 2[(tw * (d-2*tf)3) /12]               Iw =     0.137 in
Dimension: Center of Compression Flange to Centroid                   Ccf =     0.975 in
Dimension: Extreme Web Compression Fiber to Centroid                  Ccw =     0.950 in
Dimension: Extreme Tension Fiber to Centroid       Cif =    1.000 in
Dimension: Extreme Web Tension Fiber to Centroid   Ctw =    0.950 in
Allowable Compressive Bending Moment:              Mac =    3.264 kip-in Mac = ((Fbcf*If)/Ccf)+((Fbcw*Iw
Allowable Tension Bending Moment:                  Mat =   11.975 kip-in Mat = ((Fbtf*If)/Ctf)+((Fbtw*Iw

Allowable minor axis bending stress                        4.201 ksi
Maxim allowed Bending Moment May = Fby * Sy                2.878 Kip-In
SELECT member from drop down list

Weak Axis Support Distance              Enter dimension
Strong Axis Support Distance            Enter dimension
Stich screw O.C. spacing                Enter dimension

              PROPERTIES TABLE, TYPICAL SELF-MATING, OR LAP BEAM SECTIONS
                                                          Lookup Table column ID's
                       Standard AAF SMB Sections             6        7         8          9          10
                                                          Properties from Autocad (AAF Guide Appendix A, 2007 Edition)
                                b           d        tw           tf    A        Ix      Sx         rx           Iy
                   S2X4         2           4       0.046     0.100    0.782   2.000    1.000     1.600         0.470
                   S2X5         2           5       0.050     0.116    0.917   3.644    1.510     1.993         0.592
                   S2X6         2           6       0.050     0.120    1.022   5.660    1.944     2.354         0.685
                   S2X7         2           7       0.055     0.120    1.229   8.472    2.420     2.626         0.849
                   S2X8         2           8       0.072     0.224    1.847   16.557   4.139     2.994         1.215
                   S2X9         2           9       0.082     0.306    2.357   27.16    6.036     3.395         1.524
                  S2X10         2          10       0.092     0.374    3.013   42.282   8.456     3.746         1.926

Summary of Results for Section and Dimensions Considered:
             Fc         Fa       Fbx    Mx      Fby    My
                  1.863        1.904     6.040     14.502     4.201    2.878
[Allowable Stress values in ksi; Fa in kips; Moments in kip-in]
Weight/ft of Section Considered:                      1.228 lbs/ft

                                                                                                Screw Spacing
                                                                                                    24
                                                                                                    20
                                                                                                    16
                                                                                                    12
Mac = ((Fbcf*If)/Ccf)+((Fbcw*Iw)/Ccw)
Mat = ((Fbtf*If)/Ctf)+((Fbtw*Iw)/Ctw)
Section 4.7.3 Governed by Flange Compression
Section 4.7.3 Governs
Mac = ((Fbcf*If)/Ccf)+((Fbcw*Iw)/Ccw)
Mat = ((Fbtf*If)/Ctf)+((Fbtw*Iw)/Ctw)
                  11      12
endix A, 2007 Edition)
                  Sy       ry
                0.471    0.775
                0.592    0.800
                0.685    0.819
                0.850    0.831
                1.215    0.8109
                1.526    0.804
                1.926     0.8




                2X10
                 109     0.0%
                114.4    5.0%
                119.7    9.8%
                125.1    14.8%
          This Calculation for Stitched SMB 6063T6 Sections

           Select Self-Mating Beam Section                           S2X4          SELECT member from dro

Weak axis (Y) un-braced Beam length (purlin spacing)        Enter:    96.000 in    Weak Axis Support Distance
Strong (X) axis support length (total unsupported length)   Enter:   123.960 in    Strong Axis Support Distance
Spacing of Flange Stitch Screws                             Enter:    24.000 in    Stich screw O.C. spacing


Self-Mating Profile Dimensions and Properties
Width b                                                               2.000 in
Height d                                                              4.000 in
Channel Flange Width bf used to calculate buckling                     1.514 in
Channel Flange Width bc                                                1.560 in
Web Height used for Buckling h = d - 2tf                               3.800 in
Flange Thickness tf                                                   0.100 in
Web thickness tw                                                      0.046 in
                                                                               2
Total Area (A)                                                         0.782 in
                                                                               2
Web Area ( Aw )                                                        0.350 in
                                                                               2
Flange Area (Af)                                                       0.400 in
                                                                               4
Torsional Constant (J)                                                 1.113 in
                                                                               4
Moment Of Inertia X-Axis Ix                                            2.000 in
                                                                               3
Section Modulus X-Axis Sx                                              1.000 in    Summary of Results for S
Radius of Gyration X-Axis rx                                           1.600 in     Member
                                                                               4
Moment Of Inertia Y-Axis Iy                                            0.470 in        S2X4
                                                                               3
Section Modulus Y-Axis Sy                                              0.471 in    [Allowable Stress values in ksi;
Radius of Gyration Y-Axis ry                                           0.775 in    Weight/ft of Section Conside

Open Channel properties - In weak axis
Channel Height dc                                                      3.950 in
Distance to the center of gravity from Outer Web Edge C1               0.378 in
To the other edge C2 - (bf -C1)                                        1.182 in
                                                                               4
Moment Inertia in weak axis Iyc                                        0.079 in
Radius of Gyration ryc                                                 0.488 in
                                                                               2
Cross section area                                                     0.333 in

               Allowable Major Axis Bending Moment

                         Tension
Tension 3.4.2 (Flat elements in Uniform Tension)            Fbtf     15.000
Tension 3.4.4 (Flat elements bending in their own plane)    Fbtw     20.000

                         Compression
Member Buckling 3.4.14
S = 2*Lb * Sx / SQRT( Iy * J) (Lb is Un-braced length)                 265.422
IF S <= 130 Then Fbcx = 15 ksi
IF S > 130 AND < 2400 Then Fbcx = (16.7 - 0.14) * S0.5
IF S >= 2400 Then Fbcx = 23,600/S
                                                Actual Fbcx            14.419 ksi
                Allowable Moment based upon 3.4.14                     14.419 kip-in

Member Buckling Between Stitch Screws 3.4.11
Lb - Stitch screw spacing
ryc - Minor axis radius of gyration
S= Lb / ryc                                                            49.220
IF S <= 22 Then Fbcxh = 15 ksi
IF S > 22 AND S < 94 Then Fbcxw = 16.7 - 0.073* S
IF S >= 94 Then Fcbxw = 87,000/S2
                                               Actual Fbcxh            13.107
                Allowable Moment based upon 3.4.11                     13.107 kip-in

Web Local Buckling 3.4.18
S=h/tw                                                                  82.609
IF S <= 53 Then Fbcxw = 20 ksi
IF S > 53 AND S < 90 Then Fbcxw = 27.9 - 0.155* S
IF S >= 90 Then Fcbxw = 1260/S
                                               Actual Fbcxw             15.096

Flange Local Buckling 3.4.15
S=2bf/tf                                                                30.280
IF S <= 7.2 Then Fbcxf = 15 ksi
IF S > 7.2 AND S < 12 Then Fbcxf = 19.0 - 0.541*S ksi
IF S >= 12 Then Fbcxf = 152/S ksi
                                                Actual Fcbxf             5.020

Maximum allowed bending stress Fbx (Section 3.4)                        5.020 ksi

Allowable Bending Moment per Section 4.7.3
                                                                                 4
Flange Group If = 2[(b*tf3 / 12) + b*tf*(d/2-tf/2)2]            If =     1.521 in
                                                                                 4
Web Group Moment of Inertia Iw = 2[(tw * (d-2*tf)3) /12]        Iw =     0.421 in
Dimension: Center of Compression Flange to Centroid            Ccf =     1.954 in
Dimension: Extreme Web Compression Fiber to Centroid           Ccw =     1.908 in
Dimension: Extreme Tension Fiber to Centroid                   Cif =     2.000 in
Dimension: Extreme Web Tension Fiber to Centroid               Ctw =     1.908 in
Allowable Compressive Bending Moment:                          Mac =     7.237 kip-in Mac = ((Fbcf*If)/Ccf)+((Fbcw*Iw
Allowable Tension Bending Moment:                              Mat =    15.820 kip-in Mat = ((Fbtf*If)/Ctf)+((Fbtw*Iw
Allowable Major Axis Moment based upon Beam Half Buckling        13.1    Kip-In
Average Allowable Bending Stress for 4.7.3 method:                7.2    ksi
Maximum Allowable Major Axis Moment (Section 3.4)                 5.0    Kip-In
Maximum Allowable Major Axis Moment (Paragraph 4.7.3)             7.2    Kip-In Section 4.7.3 Governed by Fl
Maximum allowed Bending Moment (three methods)                    7.2    Kip-In Section 4.7.3 Governs


                          Axial Compression (Fc)

Member Buckling (ADM Specification 3.4.7)
Sx=kL/rx - k is assumed 1 worst case                            77.475
Sy=kL/ry - k is assumed 1 worst case                           123.871
S=kL/r (Larger of x or y axis)                                 123.871
[S=slenderness ratio]
If S < 78 then Fcm = 14.2 – 0.074 * S
If S >= 78 then Fcm = 51,100/S2
                                               Actual Fcm       3.330

Beam Half, Member Buckling between stitch screws (ADM 3.4.7)
k=0.5, L = Stitch spacing
ryc = Minor axis radius of gyration of section half
S = kL/ryc k = 0.5, L = 24.0 in                                 24.610
If S < 78 then Fch = 14.2 – 0.074 * S
If S >= 78 then Fch = 51,100/S2
                                               Actual Fch      12.379

Flange Local Buckling (ADM Specification 3.4.8.1)
S = 2*bf/tf                                                     30.280
if S <= 2.1 Then Fcf (ksi) = 15
if S > 2.1 AND < 14 Then Fcf (ksi) = 16.1 - 0.458 *S
if S >= 14 Then Fcf (ksi) = 1970/S2
                                                Actual Fcf      2.149

Web Local Buckling (ADM Specification 3.4.9)
S=h/tw                                                          82.609
If S <= 6.7 Then Fcw (ksi.) = 15
If S > 6.7 AND < 39 Then Fcw (ksi) = 16.1 - 0.144 * S
If S >= 39 Then Fcw (ksi) = 410/S
                                               Actual Fcw       4.963

Weighted Average Web / Flange Local Buckling (ADM 4.7.2)
Fca = (Fcw*Aw + Fcf*Af)/ A                                      3.317
Member Buckling Elastic (ADM 4.7.4)
Fec = π2E/(kL/r)2 ksi (Eq. 4.7.4-3)                         6.497

Web Local Elastic Buckling (ADM Specification 4.7.1-1)
Fcrw (ksi) = π2*E/(1.6*S)2                                  5.706

Flange Local Elastic Buckling (ADM Specification 3.4.8.1)
Fcrf = π2*E/(5.1*S)2                                        4.180

Interaction Between Local and Member Buckling 4.7.4
The reduced member Buckling allowable stress
Frc = (Fec)1/3 * (Fcr)2/3 / nu.. nu = 1.95
Fec = Elastic member buckling                               3.330
Fcr = Minimum Elastic Local Buckling                        4.180
nu = Structural factor of safety                            1.950
IF Fcr /nu < Fec Then Frc = (Fec)1/3 * (Fcr)2/3 / nu        2.483

Maximum allowable Axial compressive stress                  2.149 ksi
Allowable Axial Compression                                 1.681 k
SELECT member from drop down list

Weak Axis Support Distance              Enter dimension
Strong Axis Support Distance            Enter dimension
Stich screw O.C. spacing                Enter dimension

              PROPERTIES TABLE, TYPICAL SELF-MATING, OR LAP BEAM SECTIONS
                                                          Lookup Table column ID's
                       Standard AAF SMB Sections             6        7         8          9          10
                                                          Properties from Autocad (AAF Guide Appendix A, 2007 Edition)
                                b           d        tw           tf    A        Ix      Sx         rx           Iy
                   S2X4         2           4       0.046     0.100    0.782   2.000    1.000     1.600         0.470
                   S2X5         2           5       0.050     0.116    0.917   3.644    1.510     1.993         0.592
                   S2X6         2           6       0.050     0.120    1.022   5.660    1.944     2.354         0.685
                   S2X7         2           7       0.055     0.120    1.229   8.472    2.420     2.626         0.849
                   S2X8         2           8       0.072     0.224    1.847   16.557   4.139     2.994         1.215
                   S2X9         2           9       0.082     0.306    2.357   27.16    6.036     3.395         1.524
                  S2X10         2          10       0.092     0.374    3.013   42.282   8.456     3.746         1.926

Summary of Results for Section and Dimensions Considered:
             Fc         Fa       Fbx    Mx      Fby    My
                  2.149        1.681     5.020      7.237     0.000    0.000
[Allowable Stress values in ksi; Fa in kips; Moments in kip-in]
Weight/ft of Section Considered:                      0.940 lbs/ft

                                                                                                Screw Spacing
                                                                                                    24
                                                                                                    20
                                                                                                    16
                                                                                                    12
Mac = ((Fbcf*If)/Ccf)+((Fbcw*Iw)/Ccw)
Mat = ((Fbtf*If)/Ctf)+((Fbtw*Iw)/Ctw)
Section 4.7.3 Governed by Flange Compression
Section 4.7.3 Governs
                  11      12
endix A, 2007 Edition)
                  Sy       ry
                0.471    0.775
                0.592    0.800
                0.685    0.819
                0.850    0.831
                1.215    0.8109
                1.526    0.804
                1.926     0.8




                2X10
                 109     0.0%
                114.4    5.0%
                119.7    9.8%
                125.1    14.8%
     This Calculation for Stitched SMB Sections of 6005T5 OR 6061T6

                     Select SMB Section                               S2X9

Weak axis (Y) un-braced Beam length (purlin spacing)         Enter:    84.000 in    Weak Axis Support Distance
Strong (X) axis support length (total unsupported length)    Enter:   314.880 in    Strong Axis Support Distance
Spacing of Flange Stitch Screws                              Enter:    24.000 in    (24" Spacing OK for all SMB's

SMB as closed section
Width b                                                                2.000 in
Height d                                                               9.000 in
Channel Flange Width bf used to calculate buckling                      1.478 in
Channel Flange Width bc                                                 1.560 in
Web Height used for Buckling h = d - 2tf                                8.388 in
Flange Thickness tf                                                    0.306 in
Web thickness tw                                                       0.082 in
                                                                                2
Total Area (A)                                                          2.357 in
                                                                                2
Web Area ( Aw )                                                         1.376 in
                                                                                2
Flange Area (Af)                                                        1.224 in
                                                                                4
Tort ional Constant (J)                                                 4.952 in
                                                                                4
Moment Of Inertia X-Axis Ix                                            27.160 in
                                                                                3
Section Modulus X-Axis Sx                                               6.036 in
Radius of Gyration X-Axis rx                                            3.395 in
                                                                                4
Moment Of Inertia Y-Axis Iy                                             1.524 in
                                                                                3
Section Modulus Y-Axis Sy                                               1.526 in
Radius of Gyration Y-Axis ry                                            0.804 in

Open Channel properties - In weak axis
Channel Height dc                                                       8.847 in
Distance to the center of gravity from Outer Web Edge C1                0.341 in
To the other edge C2 - (bf -C1)                                         1.219 in
                                                                                4
Moment Inertia in weak axis Iyc                                         0.252 in
Radius of Gyration ryc                                                  0.463 in
                                                                                2
Cross section area                                                      1.178 in

               Allowable Major Axis Bending Moment

                         Tension
Tension 3.4.2 (Flat elements in Uniform Tension)            Fbtf       19.000 ksi
Tension 3.4.4 (Flat elements bending in their own plane)    Fbtw       28.000 ksi

                         Compression
Member Buckling 3.4.14
S = 2*Lb * Sx / SQRT( Iy * J) (Lb is Un-braced length)                 369.085 Ratio
IF S <= 123 Then Fbcx = 21 ksi
IF S > 123 AND < 1,680 Then Fbcx = (23.9 - 0.238) * S0.5
IF S >= 1,680 Then Fbcx = 23,600/S
                                               Actual Fbcx             19.328 ksi
    Allowable Moment from Member Buckling 3.4.14                      116.653

Member Buckling Between Stitch Screws 3.4.11
Lb - Stitch screw spacing
ryc - Minor axis radius of gyration
S= Lb / ryc                                                            51.860 Ratio
IF S <= 21 Then Fbcxh = 21 ksi
IF S > 21 AND S < 79 Then Fbcxw = 23.9 - 0.124* S
IF S >= 79 Then Fcbxw = 87,000/S2
                                               Actual Fbcxh            17.469 ksi

Web Local Buckling 3.4.18
S=h/tw                                                                 102.293 Ratio
IF S <= 48 Then Fbcxw = 28 ksi
IF S > 48 AND S < 75 Then Fbcxw = 40.5 - 0.270* S
IF S >= 75 Then Fcbxw = 1520/S
                                             Actual Fbcxw               14.859 ksi

Flange Local Buckling 3.4.15
S=2bf/tf                                                                 9.660 Ratio
IF S <= 6.5 Then Fbcxf = 21 ksi
IF S > 6.5 AND S < 10 Then Fbcxf = 27.3 - 0.930*S ksi
IF S >= 10 Then Fbcxf = 182/S ksi
                                               Actual Fcbxf             18.316 ksi

Maximum allowed bending stress Fbx (Section 3.4)                       14.859 ksi

Allowable Bending Moment per Section 4.7.3
                                                                                 4
Flange Group Moment of Inertia                                 If =     23.139 in
                                                                                 4
Web Group Moment of Inertia                                    Iw =      8.066 in
Dimension: Center of Compression Flange to Centroid           Ccf =      4.418 in
Dimension: Extreme Web Compression Fiber to Centroid          Ccw =      4.336 in
Dimension: Extreme Tension Fiber to Centroid                  Cif =      4.500 in
Dimension: Extreme Web Tension Fiber to Centroid              Ctw =      4.336 in
Allowable Compressive Bending Moment:                         Mac =    123.569 kip-in
Allowable Tension Bending Moment:                             Mat =    149.781 kip-in
Maximum Allowable Major Axis Moment (Paragraph 4.7.3)                 123.569 Kip-In Section 4.7.3 Governed by Fl
Average Allowable Bending Stress for 4.7.3 method:               20.473   ksi
Allowable Major Axis Moment based upon Beam Half Buckling      105.437    Kip-In
Maximum Allowable Major Axis Moment (Section 3.4)               89.684    Kip-In
Maximum allowed Bending Moment (three methods)                 105.437    Kip-InBeam Half Member Buckl
Maximum allowed bending stress Fb                               17.469    ksi


                          Axial Compression (Fc)

Member Buckling (ADM Specification 3.4.7)
Sx=kL/rx - k is assumed 1 worst case                             92.748 Ratio
Sy=kL/ry - k is assumed 1 worst case                            104.478 Ratio
S=kL/r (Larger of x or y axis)                                  104.478 Ratio
[S=slenderness ratio]
If S < 66 then Fcm = 20.2 – 0.126 * S
If S >= 66 then Fcm = 51,100/S2
                                               Actual Fcm        4.681 ksi

Beam Half, Member Buckling between stitch screws (ADM 3.4.7)
k=0.5, L = Stitch spacing
ryc = Minor axis radius of gyration of section half
S = kL/ryc k = 0.5, L = 24.0 in                                  25.930 Ratio
If S < 66 then Fcm = 20.2 – 0.126 * S
If S >= 66 then Fcm = 51,100/S2
                                               Actual Fch       16.933 ksi

Flange Local Buckling (ADM Specification 3.4.8.1)
S = 2*bf/tf                                                       9.660 Ratio
if S <= 2.4 Then Fcf (ksi) = 21
if S > 2.4 AND < 12 Then Fcf (ksi) = 23.1 - 0.787 *S
if S >= 12 Then Fcf (ksi) = 1970/S2
                                                Actual Fcf      15.497 ksi

Web Local Buckling (ADM Specification 3.4.9)
S=h/tw                                                          102.293 Ratio
If S <= 7.6 Then Fcw (ksi.) = 21
If S > 7.6 AND < 33 Then Fcw (ksi) = 23.1 - 0.247 * S
If S >= 33 Then Fcw (ksi) = 491/S
                                               Actual Fcw        4.800 ksi

Weighted Average Web / Flange Local Buckling (ADM 4.7.2)
Fca = (Fcw*Aw + Fcf*Af)/ A                                      10.849 ksi

Member Buckling Elastic (ADM 4.7.4)
Fec = π2E/(kL/r)2 ksi (Eq. 4.7.4-3)                                                      9.132 ksi

Web Local Elastic Buckling (ADM Specification 4.7.1-1)
Fcrw (ksi) = π2*E/(1.6*S)2                                                               3.721 ksi

Flange Local Elastic Buckling (ADM Specification 3.4.8.1)
Fcrf = π2*E/(5.1*S)2                                                                    41.069 ksi

Interaction Between Local and Member Buckling 4.7.4
The reduced member Buckling allowable stress
Frc = (Fec)1/3 * (Fcr)2/3 / nu.. nu = 1.95
Fec = Elastic member buckling                                                             4.681 ksi
Fcr = Minimum Elastic Local Buckling                                                      3.721 ksi
nu = Structural factor of safety                                                          1.950 ksi
                                    1/3             2/3
IF Fcr /nu < Fec Then Frc = (Fec)         * (Fcr)         / nu                           2.574 ksi

Maximum allowable Axial compressive stress                                               2.574 ksi
Allowable Axial Compression                                                              6.067 k

                 Allowable Stress: Minor Axis Bending

Tension 3.4.4
Fbty                                                                                     28.000 ksi

Web Local Buckling 3.4.16
S=h/tw                                                                                  102.293 Ratio
IF S <= 21 Then Fbcyw = 21 ksi
IF S > 21 AND S < 33 Then Fbcyw = 27.3 - 0.292* S
IF S >= 33 Then Fcbyw = 580/S
                                                             Actual Fbcxw                 5.670 ksi

Flange Local Buckling 3.4.17
S=2bf/tf                                                                                  9.660
IF S <= 9.1 Then Fbcyf = 28 ksi
IF S > 9.1 AND S < 19 Then Fbcyf = 40.5 - 1.41*S ksi
IF S >= 19 Then Fbcyf = 4930/S2 ksi
                                                                 Actual Fcbxf            26.879 ksi

Allowable Bending Moment per Section 4.7.3
                                                                                                  4
Flange Group If = 2[(b*tf3 / 12) + b*tf*(d/2-tf/2)2]                             If =     1.231 in
                                                                                                  4
Web Group Moment of Inertia Iw = 2[(tw * (d-2*tf)3) /12]                         Iw =     0.316 in
Dimension: Center of Compression Flange to Centroid                             Ccf =     0.959 in
Dimension: Extreme Web Compression Fiber to Centroid                            Ccw =     0.918 in
Dimension: Extreme Tension Fiber to Centroid                                    Cif =     1.000 in
Dimension: Extreme Web Tension Fiber to Centroid   Ctw =    0.918 in
Allowable Compressive Bending Moment:              Mac =   16.451 kip-in Mac = ((Fbcf*If)/Ccf)+((Fbcw*Iw
Allowable Tension Bending Moment:                  Mat =   41.006 kip-in Mat = ((Fbtf*If)/Ctf)+((Fbtw*Iw

Allowable minor axis bending stress                        16.451 ksi
Maxim allowed Bending Moment May = Fby * Sy                25.105 Kip-In
Weak Axis Support Distance
Strong Axis Support Distance
(24" Spacing OK for all SMB's up to 2X9, best results for 2X9 & 2X10 require 16" stitch spacing)

              PROPERTIES TABLE, TYPICAL SELF-MATING, OR LAP BEAM SECTIONS
                                                        Lookup Table column ID's
                      Standard AAF SMB Sections            6        7         8          9          10
                                                        Properties from Autocad (AAF Guide Appendix A, 2007 Edition)
                                 b          d       tw        tf        A         Ix      Sx       rx     Iy
                  S2X4           2          4      0.046    0.100     0.782     2.000    1.000   1.600   0.470
                  S2X5           2          5      0.050    0.116     0.917     3.644    1.510   1.993   0.592
                  S2X6           2          6      0.050    0.120     1.022     5.660    1.944   2.354   0.685
                  S2X7           2          7      0.055    0.120     1.229     8.472    2.425   2.626   0.849
                  S2X8           2          8      0.072    0.224     1.847     16.557   4.441   2.994   1.215
                  S2X9           2          9      0.082    0.306     2.357     27.16    6.123   3.395   1.524
                  S2X10          2         10      0.092    0.374     3.013     42.282   8.462   3.746   1.926

              Maximum stitch screw spacing =                   6.06




              Summary of Results for Section and Dimensions Considered:
               Member      Fc        Fa    Fbx     Mx    Fby    My
                  S2X9         2.574      6.067 17.469 105.437 16.451 25.105
              [Allowable Stress values in ksi; Fa in kips; Moments in kip-in]


              Weight/ft of Section Considered:                2.832 lbs/ft
Section 4.7.3 Governed by Flange Compression
Beam Half Member Buckling Governs
Mac = ((Fbcf*If)/Ccf)+((Fbcw*Iw)/Ccw)
Mat = ((Fbtf*If)/Ctf)+((Fbtw*Iw)/Ctw)
                  11      12
endix A, 2007 Edition)
                  Sy       ry
                0.471    0.775
                0.592    0.800
                0.685    0.819
                0.850    0.831
                1.215    0.8109
                1.526    0.804
                1.926     0.8
     This Calculation for Stitched SMB Sections of 6005T5 OR 6061T6

                     Select SMB Section                               S2X5

Weak axis (Y) un-braced Beam length (purlin spacing)         Enter:    84.000 in    Weak Axis Support Distance
Strong (X) axis support length (total unsupported length)    Enter:   123.960 in    Strong Axis Support Distance
Spacing of Flange Stitch Screws                              Enter:    24.000 in    (24" Spacing OK for all SMB's

SMB as closed section
Width b                                                                2.000 in
Height d                                                               5.000 in
Channel Flange Width bf used to calculate buckling                      1.510 in
Channel Flange Width bc                                                 1.560 in
Web Height used for Buckling h = d - 2tf                                4.768 in
Flange Thickness tf                                                    0.116 in
Web thickness tw                                                       0.050 in
                                                                                2
Total Area (A)                                                          0.917 in
                                                                                2
Web Area ( Aw )                                                         0.477 in
                                                                                2
Flange Area (Af)                                                        0.464 in
                                                                                4
Tort ional Constant (J)                                                 1.584 in
                                                                                4
Moment Of Inertia X-Axis Ix                                             3.644 in
                                                                                3
Section Modulus X-Axis Sx                                               1.510 in
Radius of Gyration X-Axis rx                                            1.993 in
                                                                                4
Moment Of Inertia Y-Axis Iy                                             0.592 in
                                                                                3
Section Modulus Y-Axis Sy                                               0.592 in
Radius of Gyration Y-Axis ry                                            0.800 in

Open Channel properties - In weak axis
Channel Height dc                                                       4.942 in
Distance to the center of gravity from Outer Web Edge C1                0.349 in
To the other edge C2 - (bf -C1)                                         1.211 in
                                                                                4
Moment Inertia in weak axis Iyc                                         0.096 in
Radius of Gyration ryc                                                  0.476 in
                                                                                2
Cross section area                                                      0.422 in

               Allowable Major Axis Bending Moment

                         Tension
Tension 3.4.2 (Flat elements in Uniform Tension)            Fbtf       19.000 ksi
Tension 3.4.4 (Flat elements bending in their own plane)    Fbtw       28.000 ksi

                         Compression
Member Buckling 3.4.14
S = 2*Lb * Sx / SQRT( Iy * J) (Lb is Un-braced length)                262.018 Ratio
IF S <= 123 Then Fbcx = 21 ksi
IF S > 123 AND < 1,680 Then Fbcx = (23.9 - 0.238) * S0.5
IF S >= 1,680 Then Fbcx = 23,600/S
                                               Actual Fbcx            20.048 ksi
    Allowable Moment from Member Buckling 3.4.14                      30.272

Member Buckling Between Stitch Screws 3.4.11
Lb - Stitch screw spacing
ryc - Minor axis radius of gyration
S= Lb / ryc                                                           50.415 Ratio
IF S <= 21 Then Fbcxh = 21 ksi
IF S > 21 AND S < 79 Then Fbcxw = 23.9 - 0.124* S
IF S >= 79 Then Fcbxw = 87,000/S2
                                               Actual Fbcxh           17.649 ksi

Web Local Buckling 3.4.18
S=h/tw                                                                 95.360 Ratio
IF S <= 48 Then Fbcxw = 28 ksi
IF S > 48 AND S < 75 Then Fbcxw = 40.5 - 0.270* S
IF S >= 75 Then Fcbxw = 1520/S
                                             Actual Fbcxw              15.940 ksi

Flange Local Buckling 3.4.15
S=2bf/tf                                                               26.034 Ratio
IF S <= 6.5 Then Fbcxf = 21 ksi
IF S > 6.5 AND S < 10 Then Fbcxf = 27.3 - 0.930*S ksi
IF S >= 10 Then Fbcxf = 182/S ksi
                                               Actual Fcbxf             6.991 ksi

Maximum allowed bending stress Fbx (Section 3.4)                       6.991 ksi

Allowable Bending Moment per Section 4.7.3
                                                                                4
Flange Group Moment of Inertia                                 If =     2.768 in
                                                                                4
Web Group Moment of Inertia                                    Iw =     0.903 in
Dimension: Center of Compression Flange to Centroid           Ccf =     2.450 in
Dimension: Extreme Web Compression Fiber to Centroid          Ccw =     2.400 in
Dimension: Extreme Tension Fiber to Centroid                  Cif =     2.500 in
Dimension: Extreme Web Tension Fiber to Centroid              Ctw =     2.400 in
Allowable Compressive Bending Moment:                         Mac =    13.896 kip-in
Allowable Tension Bending Moment:                             Mat =    31.572 kip-in
Maximum Allowable Major Axis Moment (Paragraph 4.7.3)                 13.896 Kip-In Section 4.7.3 Governed by Fl
Average Allowable Bending Stress for 4.7.3 method:               9.203   ksi
Allowable Major Axis Moment based upon Beam Half Buckling      26.649    Kip-In
Maximum Allowable Major Axis Moment (Section 3.4)              10.556    Kip-In
Maximum allowed Bending Moment (three methods)                 13.896    Kip-InSection 4.7.3 governs
Maximum allowed bending stress Fb                               9.203    ksi


                          Axial Compression (Fc)

Member Buckling (ADM Specification 3.4.7)
Sx=kL/rx - k is assumed 1 worst case                            62.198 Ratio
Sy=kL/ry - k is assumed 1 worst case                           105.000 Ratio
S=kL/r (Larger of x or y axis)                                 105.000 Ratio
[S=slenderness ratio]
If S < 66 then Fcm = 20.2 – 0.126 * S
If S >= 66 then Fcm = 51,100/S2
                                               Actual Fcm       4.635 ksi

Beam Half, Member Buckling between stitch screws (ADM 3.4.7)
k=0.5, L = Stitch spacing
ryc = Minor axis radius of gyration of section half
S = kL/ryc k = 0.5, L = 24.0 in                                 25.207 Ratio
If S < 66 then Fcm = 20.2 – 0.126 * S
If S >= 66 then Fcm = 51,100/S2
                                               Actual Fch      17.024 ksi

Flange Local Buckling (ADM Specification 3.4.8.1)
S = 2*bf/tf                                                     26.034 Ratio
if S <= 2.4 Then Fcf (ksi) = 21
if S > 2.4 AND < 12 Then Fcf (ksi) = 23.1 - 0.787 *S
if S >= 12 Then Fcf (ksi) = 1970/S2
                                                Actual Fcf      2.906 ksi

Web Local Buckling (ADM Specification 3.4.9)
S=h/tw                                                          95.360 Ratio
If S <= 7.6 Then Fcw (ksi.) = 21
If S > 7.6 AND < 33 Then Fcw (ksi) = 23.1 - 0.247 * S
If S >= 33 Then Fcw (ksi) = 491/S
                                               Actual Fcw       5.149 ksi

Weighted Average Web / Flange Local Buckling (ADM 4.7.2)
Fca = (Fcw*Aw + Fcf*Af)/ A                                      4.146 ksi

Member Buckling Elastic (ADM 4.7.4)
Fec = π2E/(kL/r)2 ksi (Eq. 4.7.4-3)                              9.042 ksi

Web Local Elastic Buckling (ADM Specification 4.7.1-1)
Fcrw (ksi) = π2*E/(1.6*S)2                                       4.282 ksi

Flange Local Elastic Buckling (ADM Specification 3.4.8.1)
Fcrf = π2*E/(5.1*S)2                                             5.654 ksi

Interaction Between Local and Member Buckling 4.7.4
The reduced member Buckling allowable stress
Frc = (Fec)1/3 * (Fcr)2/3 / nu.. nu = 1.95
Fec = Elastic member buckling                                    4.635 ksi
Fcr = Minimum Elastic Local Buckling                             4.282 ksi
nu = Structural factor of safety                                 1.950 ksi
                                    1/3             2/3
IF Fcr /nu < Fec Then Frc = (Fec)         * (Fcr)         / nu   2.817 ksi

Maximum allowable Axial compressive stress                       2.817 ksi
Allowable Axial Compression                                      2.584 k
Weak Axis Support Distance
Strong Axis Support Distance
(24" Spacing OK for all SMB's up to 2X9, best results for 2X9 & 2X10 require 16" stitch spacing)

              PROPERTIES TABLE, TYPICAL SELF-MATING, OR LAP BEAM SECTIONS
                                                        Lookup Table column ID's
                      Standard AAF SMB Sections            6        7         8          9          10
                                                        Properties from Autocad (AAF Guide Appendix A, 2007 Edition)
                                 b          d       tw        tf        A         Ix      Sx       rx     Iy
                  S2X4           2          4      0.046    0.100     0.782     2.000    1.000   1.600   0.470
                  S2X5           2          5      0.050    0.116     0.917     3.644    1.510   1.993   0.592
                  S2X6           2          6      0.050    0.120     1.022     5.660    1.944   2.354   0.685
                  S2X7           2          7      0.055    0.120     1.229     8.472    2.425   2.626   0.849
                  S2X8           2          8      0.072    0.224     1.847     16.557   4.441   2.994   1.215
                  S2X9           2          9      0.082    0.306     2.357     27.16    6.123   3.395   1.524
                  S2X10          2         10      0.092    0.374     3.013     42.282   8.462   3.746   1.926

              Maximum stitch screw spacing =                   4.16




              Summary of Results for Section and Dimensions Considered:
               Member      Fc        Fa    Fbx     Mx    Fby    My
                  S2X5         2.817      2.584    9.203   13.896     0.000     0.000
              [Allowable Stress values in ksi; Fa in kips; Moments in kip-in]


              Weight/ft of Section Considered:                1.102 lbs/ft
Section 4.7.3 Governed by Flange Compression
Section 4.7.3 governs
                  11      12
endix A, 2007 Edition)
                  Sy       ry
                0.471    0.775
                0.592    0.800
                0.685    0.819
                0.850    0.831
                1.215    0.8109
                1.526    0.804
                1.926     0.8

				
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