V. AISC 360-10 Pipe F.9
Verify the available flexural strength of a compact pipe member per the AISC 360-10 code.
Details
From reference (2):
Select an ASTM A53 Grade B Pipe shape with an 8-in. nominal depth and a simple span of 16 ft. The loads are a total uniform dead load of 0.32 kip/ft and a uniform live load of 0.96 kip/ft. 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: (Compact)
By observation, , so Section F8 applies.
| (F8-1) |
The available flexural strength:
LRFD:
ASD:
Results
| Result Type | Reference | STAAD.Pro | Difference | Comments |
|---|---|---|---|---|
| ϕbMn (ft·k) [LRFD] | 81.4 | 81.4 | none | |
| Mn/Ωb (ft·k) [ASD] | 54.1 | 54.1 | none |
STAAD.Pro Input
The file C:\Users\Public\Public Documents\STAAD.Pro CONNECT Edition\Samples\ Verification Models\09 Steel Design\US\AISC\AISC 360-10 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
LOAD 1 LOADTYPE None TITLE LOAD CASE 1
MEMBER LOAD
1 UNI GY -0.32
LOAD 2 LOADTYPE None TITLE LOAD CASE 2
MEMBER LOAD
1 UNI GY -0.96
LOAD COMB 3 COMBINATION LOAD CASE 3
1 1.2 2 1.6
LOAD COMB 4 COMBINATION LOAD CASE 4
1 1.0 2 1.0
PERFORM ANALYSIS
LOAD LIST 3
PARAMETER 1
CODE AISC UNIFIED 2010
METHOD LRFD
FU 8640 ALL
FYLD 5040 ALL
TRACK 2 ALL
CHECK CODE ALL
LOAD LIST 4
PARAMETER 2
CODE AISC UNIFIED 2010
METHOD ASD
FU 8640 ALL
FYLD 5040 ALL
TRACK 2 ALL
CHECK CODE ALL
FINISH
STAAD.Pro Output
STAAD.PRO CODE CHECKING - (AISC-360-10-LRFD) v1.4a ******************************************** ALL UNITS ARE - KIP FEET (UNLESS OTHERWISE Noted) MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ 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(a)-9 | | Non-Slender 18.55 N/A 91.14 T.B4.1(a)-9 | | Flexure : Compact 18.55 58.00 256.86 T.B4.1(b)-20 | | Compact 18.55 58.00 256.86 T.B4.1(b)-20 | STAAD SPACE -- PAGE NO. 4 STAAD.PRO CODE CHECKING - (AISC-360-10-LRFD) v1.4a ******************************************** 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 Eq. E3-1 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-360-10-LRFD) v1.4a ******************************************** 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 | |-----------------------------------------------------------------------| 55. LOAD LIST 4 56. PARAMETER 2 57. CODE AISC UNIFIED 2010 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-360-10-ASD) v1.4a ******************************************** ALL UNITS ARE - KIP FEET (UNLESS OTHERWISE Noted) MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ 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(a)-9 | | Non-Slender 18.55 N/A 91.14 T.B4.1(a)-9 | | Flexure : Compact 18.55 58.00 256.86 T.B4.1(b)-20 | | Compact 18.55 58.00 256.86 T.B4.1(b)-20 | STAAD SPACE -- PAGE NO. 7 STAAD.PRO CODE CHECKING - ( AISC-360-10-ASD) v1.4a ******************************************** 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 Eq. E3-1 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-360-10-ASD) v1.4a ******************************************** 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 | |-----------------------------------------------------------------------|