V. AISC 360-05 Pipe F.9

References

1. Steel Construction Manual, Version 13.0, American Institute of Steel Construction, 2005
2. Design Examples, Version 13.0, American Institute of Steel Construction, 2005, Example F.9, pp.F-35,36

Details

From reference (2):

Select an ASTM A53 grade B Pipe shape with a simple span of 16 ft. The nominal loads are a total uniform dead load of 0.32 kip/ft and a uniform live load of 0.96 kip/ft. Assume there is no deflection limit for this beam. The beam is braced only at the ends.

Validation

Ultimate moment:

Service moment:

Try a pipe 8 x-strong, which has a plastic section modulus, Zx = 31.0 in3.

The yield strength, Fy = 35 ksi

Compactness ratio: λ = D/t = 18.5

Determine the slender flange ratio limit from Table B4.1b: $λ p = 0.07 E F y = 0.07 ( 29,000 ) 35 = 58.0 > λ$ (Compact)

By observation, $λ < 0.45 E F y$, so Section F8 applies.

$λ p = 2.42 E F y = 2.42 29,000 46 = 60.8 > λ$
 (F8-1)

The available flexural strength:

LRFD:

ASD:

ϕbMn (ft·k) [LRFD] 81.4 81.4 none
Mnb (ft·k) [ASD] 54.1 54.1 none

The file C:\Users\Public\Public Documents\STAAD.Pro CONNECT Edition\Samples\ Verification Models\09 Steel Design\US\AISC\AISC 360-05 Pipe F.STD is typically installed with the program.

STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 10-Jun-20
END JOB INFORMATION
INPUT WIDTH 79
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 16 0 0;
MEMBER INCIDENCES
1 1 2;
DEFINE MATERIAL START
ISOTROPIC STEEL
E 4.176e+06
POISSON 0.3
DENSITY 0.489024
ALPHA 6.5e-06
DAMP 0.03
TYPE STEEL
STRENGTH RY 1.5 RT 1.2
ISOTROPIC STEEL_50_KSI
E 4.176e+06
POISSON 0.3
DENSITY 0.489024
ALPHA 6.5e-06
DAMP 0.03
TYPE STEEL
STRENGTH FY 7200 FU 8928 RY 1.5 RT 1.2
END DEFINE MATERIAL
MEMBER PROPERTY AMERICAN
1 TABLE ST PIPX80
CONSTANTS
MATERIAL STEEL_50_KSI ALL
SUPPORTS
1 FIXED BUT MZ
2 FIXED BUT FX MZ
1 UNI GY -0.32
1 UNI GY -0.96
1 1.2 2 1.6
1 1.0 2 1.0
PERFORM ANALYSIS
PARAMETER 1
CODE AISC UNIFIED 2005
METHOD LRFD
FU 8640 ALL
FYLD 5040 ALL
TRACK 2 ALL
CHECK CODE ALL
PARAMETER 2
CODE AISC UNIFIED 2005
METHOD ASD
FU 8640 ALL
FYLD 5040 ALL
TRACK 2 ALL
CHECK CODE ALL
FINISH


                       STAAD.PRO CODE CHECKING - (AISC-360-05-LRFD)   v3.3a
********************************************
ALL UNITS ARE - KIP  FEET (UNLESS OTHERWISE Noted)
FX            MY             MZ       LOCATION
=======================================================================
1 ST   PIPX80                   (AISC SECTIONS)
PASS   Eq. H1-1b            0.755         3
0.00            0.00         -61.44        8.00
|-----------------------------------------------------------------------|
| SLENDERNESS                                                           |
| Actual Slenderness Ratio    :     66.233  L/C  :     3                |
| Allowable Slenderness Ratio :    300.000  LOC  :     8.00             |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS                                                       |
| Critical L/C  :      3    Ratio     :     0.755(PASS)                 |
|          Loc  :    8.00   Condition :   Eq. H1-1b                     |
|-----------------------------------------------------------------------|
| DESIGN FORCES                                                         |
| Fx:   0.000E+00(  ) Fy:   0.000E+00     Fz:   0.000E+00               |
| Mx:   0.000E+00     My:   0.000E+00     Mz:  -6.144E+01               |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES  (UNIT: INCH)                                      |
| Azz:   6.344E+00     Ayy:   6.344E+00     Cw:  0.000E+00              |
| Szz:   2.319E+01     Syy:   2.319E+01                                 |
| Izz:   1.000E+02     Iyy:   1.000E+02     Ix:  2.000E+02              |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES                                                   |
| Fyld:        5039.999   Fu:        8639.999                           |
|-----------------------------------------------------------------------|
| Actual Member Length:        16.000                                   |
| Design Parameters                                                     |
| Kz:    1.00 Ky:    1.00 NSF:    1.00 SLF:    1.00 CSP:   12.00        |
|-----------------------------------------------------------------------|
| SECTION CLASS  UNSTIFFENED /     λ       λp      λr        CASE       |
|                STIFFENED                                              |
| Compression :  Non-Slender    18.55     N/A     91.14    T.B4.1-15a   |
|                Non-Slender    18.55     N/A     91.14    T.B4.1-15a   |
| Flexure     :  Compact        18.55    58.00   256.86    T.B4.1-15b   |
|                Compact        18.55    58.00   256.86    T.B4.1-15b   |
STAAD SPACE                                              -- PAGE NO.    4
STAAD.PRO CODE CHECKING - (AISC-360-05-LRFD)   v3.3a
********************************************
ALL UNITS ARE - KIP  FEET (UNLESS OTHERWISE Noted)
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL TENSION                                               |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
| Yield       0.00E+00   3.75E+02   0.000      Eq. D2-1      3     0.00 |
| Rupture     0.00E+00   5.35E+02   0.000      Eq. D2-2      3     0.00 |
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL COMPRESSION                                           |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
| Maj Buck    0.00E+00   2.99E+02   0.000      Sec. E1       3     0.00 |
| Min Buck    0.00E+00   2.99E+02   0.000      Eq. E3-1      3     0.00 |
| Intermediate                                                          |
| Results     Eff Area     KL/r      Fcr        Fe         Pn           |
| Maj Buck    8.26E-02    66.23   4.03E+03   9.40E+03   3.33E+02        |
| Min Buck    8.26E-02    66.23   4.03E+03   9.40E+03   3.33E+02        |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR                                                       |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
| Local-Z     0.00E+00   1.12E+02   0.000      Eq. G6-1      3     0.00 |
| Local-Y     1.54E+01   1.12E+02   0.137      Eq. G6-1      3     0.00 |
| Intermediate                                                          |
| Results        Aw        Cv       Kv      h/tw      Vn                |
| Local-Z     8.26E-02     0.00     0.00     0.00   1.25E+02            |
| Local-Y     8.26E-02     0.00     0.00     0.00   1.25E+02            |
|-----------------------------------------------------------------------|
| CHECK FOR TORSION                                                     |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
|             0.00E+00   7.66E+01   0.000      Eq. H3-1      3     0.00 |
| Intermediate Fcr        Tn                                            |
|             3.02E+03   8.51E+01                                       |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING                                            |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
| Major       6.14E+01   8.14E+01   0.755      Eq. F8-1      3     8.00 |
| Minor       0.00E+00   8.14E+01   0.000      Eq. F8-1      3     0.00 |
| Intermediate   Mn        My                                           |
| Major       9.04E+01   0.00E+00                                       |
| Minor       9.04E+01   0.00E+00                                       |
STAAD SPACE                                              -- PAGE NO.    5
STAAD.PRO CODE CHECKING - (AISC-360-05-LRFD)   v3.3a
********************************************
ALL UNITS ARE - KIP  FEET (UNLESS OTHERWISE Noted)
|-----------------------------------------------------------------------|
| CHECK FOR FLEXURE TENS/COMP INTERACTION                               |
|                       RATIO      CRITERIA    L/C     LOC              |
| Flexure Comp          0.755      Eq. H1-1b     3     8.00             |
| Flexure Tens          0.755      Eq. H1-1b     3     8.00             |
| Intermediate         Mcx /      Mrx /      Pc /                       |
|                      Mcy        Mry        Pr                         |
| Flexure Comp         8.14E+01   6.14E+01   2.99E+02                   |
|                      8.14E+01   0.00E+00   0.00E+00                   |
| Flexure Tens         8.14E+01   6.14E+01   3.75E+02                   |
|                      8.14E+01   0.00E+00   0.00E+00                   |
|-----------------------------------------------------------------------|
56. PARAMETER 2
57. CODE AISC UNIFIED 2005
58. METHOD ASD
59. FU 8640 ALL
60. FYLD 5040 ALL
61. TRACK 2 ALL
62. CHECK CODE ALL
STEEL DESIGN
WARNING: For member#      1 the profile has been selected from HSS Rect/Round (non A1085)/Pipe
tables of AISC database. Weld type is considered to be Elect-resist-weld.
Thickness is already reduced from the table. Further reductions will not be done.
STAAD SPACE                                              -- PAGE NO.    6
STAAD.PRO CODE CHECKING - ( AISC-360-05-ASD)   v3.3a
********************************************
ALL UNITS ARE - KIP  FEET (UNLESS OTHERWISE Noted)
FX            MY             MZ       LOCATION
=======================================================================
1 ST   PIPX80                   (AISC SECTIONS)
PASS   Eq. H1-1b            0.757         4
0.00            0.00         -40.96        8.00
|-----------------------------------------------------------------------|
| SLENDERNESS                                                           |
| Actual Slenderness Ratio    :     66.233  L/C  :     4                |
| Allowable Slenderness Ratio :    300.000  LOC  :     8.00             |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS                                                       |
| Critical L/C  :      4    Ratio     :     0.757(PASS)                 |
|          Loc  :    8.00   Condition :   Eq. H1-1b                     |
|-----------------------------------------------------------------------|
| DESIGN FORCES                                                         |
| Fx:   0.000E+00(  ) Fy:   0.000E+00     Fz:   0.000E+00               |
| Mx:   0.000E+00     My:   0.000E+00     Mz:  -4.096E+01               |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES  (UNIT: INCH)                                      |
| Azz:   6.344E+00     Ayy:   6.344E+00     Cw:  0.000E+00              |
| Szz:   2.319E+01     Syy:   2.319E+01                                 |
| Izz:   1.000E+02     Iyy:   1.000E+02     Ix:  2.000E+02              |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES                                                   |
| Fyld:        5039.999   Fu:        8639.999                           |
|-----------------------------------------------------------------------|
| Actual Member Length:        16.000                                   |
| Design Parameters                                                     |
| Kz:    1.00 Ky:    1.00 NSF:    1.00 SLF:    1.00 CSP:   12.00        |
|-----------------------------------------------------------------------|
| SECTION CLASS  UNSTIFFENED /     λ       λp      λr        CASE       |
|                STIFFENED                                              |
| Compression :  Non-Slender    18.55     N/A     91.14    T.B4.1-15a   |
|                Non-Slender    18.55     N/A     91.14    T.B4.1-15a   |
| Flexure     :  Compact        18.55    58.00   256.86    T.B4.1-15b   |
|                Compact        18.55    58.00   256.86    T.B4.1-15b   |
STAAD SPACE                                              -- PAGE NO.    7
STAAD.PRO CODE CHECKING - ( AISC-360-05-ASD)   v3.3a
********************************************
ALL UNITS ARE - KIP  FEET (UNLESS OTHERWISE Noted)
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL TENSION                                               |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
| Yield       0.00E+00   2.49E+02   0.000      Eq. D2-1      4     0.00 |
| Rupture     0.00E+00   3.57E+02   0.000      Eq. D2-2      4     0.00 |
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL COMPRESSION                                           |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
| Maj Buck    0.00E+00   1.99E+02   0.000      Sec. E1       4     0.00 |
| Min Buck    0.00E+00   1.99E+02   0.000      Eq. E3-1      4     0.00 |
| Intermediate                                                          |
| Results     Eff Area     KL/r      Fcr        Fe         Pn           |
| Maj Buck    8.26E-02    66.23   4.03E+03   9.40E+03   3.33E+02        |
| Min Buck    8.26E-02    66.23   4.03E+03   9.40E+03   3.33E+02        |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR                                                       |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
| Local-Z     0.00E+00   7.48E+01   0.000      Eq. G6-1      4     0.00 |
| Local-Y     1.02E+01   7.48E+01   0.137      Eq. G6-1      4     0.00 |
| Intermediate                                                          |
| Results        Aw        Cv       Kv      h/tw      Vn                |
| Local-Z     8.26E-02     0.00     0.00     0.00   1.25E+02            |
| Local-Y     8.26E-02     0.00     0.00     0.00   1.25E+02            |
|-----------------------------------------------------------------------|
| CHECK FOR TORSION                                                     |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
|             0.00E+00   5.10E+01   0.000      Eq. H3-1      4     0.00 |
| Intermediate Fcr        Tn                                            |
|             3.02E+03   8.51E+01                                       |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING                                            |
|                                                                       |
|              FORCE     CAPACITY   RATIO      CRITERIA     L/C    LOC  |
| Major       4.10E+01   5.41E+01   0.757      Eq. F8-1      4     8.00 |
| Minor       0.00E+00   5.41E+01   0.000      Eq. F8-1      4     0.00 |
| Intermediate   Mn        My                                           |
| Major       9.04E+01   0.00E+00                                       |
| Minor       9.04E+01   0.00E+00                                       |
STAAD SPACE                                              -- PAGE NO.    8
STAAD.PRO CODE CHECKING - ( AISC-360-05-ASD)   v3.3a
********************************************
ALL UNITS ARE - KIP  FEET (UNLESS OTHERWISE Noted)
|-----------------------------------------------------------------------|
| CHECK FOR FLEXURE TENS/COMP INTERACTION                               |
|                       RATIO      CRITERIA    L/C     LOC              |
| Flexure Comp          0.757      Eq. H1-1b     4     8.00             |
| Flexure Tens          0.757      Eq. H1-1b     4     8.00             |
| Intermediate         Mcx /      Mrx /      Pc /                       |
|                      Mcy        Mry        Pr                         |
| Flexure Comp         5.41E+01   4.10E+01   1.99E+02                   |
|                      5.41E+01   0.00E+00   0.00E+00                   |
| Flexure Tens         5.41E+01   4.10E+01   2.49E+02                   |
|                      5.41E+01   0.00E+00   0.00E+00                   |
|-----------------------------------------------------------------------|