V. AISC 360-10 Pipe E.11
Verify the compressive strength of a pipe section braced at the midpoint in the Y-Y direction per the LRFD and ADS methods of the AISC 360-10 codes.
References
- American Institute of Steel Construction. 2010 Steel Construction Manual. Fourteenth Edition. AISC: Chicago, IL.
-
American Institute of Steel Construction. 2011. Design Examples, Version 14.0. AISC:Chicago, IL. Example E.11, pp. E-54 - E-56
Details
From reference (2):
Select an ASTM A53 Grade B Pipe compression member with a length of 30 ft to support a dead load of 35 kips and live load of 105 kips in axial compression. The column is pin-connected at the ends in both axes and braced at the midpoint in the y-y direction.
Validation
Ultimate load:
Service load:
Per Table C-A-7.1 in Reference 1, K = 1.0 for pinned-pinned columns.
So buckling about the x-x axis governs. For 35 ksi, no pipe sections are slender per Table 4-6 in Reference 1.
The critical stress
Nominal Compressive Strength
The available compressive strength:
LRFD:
ASD:
Results
Result Type | Reference | STAAD.Pro | Difference | Comments |
---|---|---|---|---|
ϕcPn (kips) [LRFD] | 221 | 219 | negligible | |
Pn/Ωc (kips) [ASD] | 147 | 145 | negligible |
STAAD.Pro Input
The file C:\Users\Public\Public Documents\STAAD.Pro 2024\Samples \Verification Models\09 Steel Design\US\AISC\AISC 360-10 Pipe E.11.STD is typically installed with the program.
STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 05-Feb-19
END JOB INFORMATION
INPUT WIDTH 79
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 0 30 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
ISOTROPIC STEEL_36_KSI
E 4.176e+06
POISSON 0.3
DENSITY 0.489024
ALPHA 6.5e-06
DAMP 0.03
TYPE STEEL
STRENGTH FY 5184 FU 8352 RY 1.5 RT 1.2
END DEFINE MATERIAL
MEMBER PROPERTY AMERICAN
1 TABLE ST PIPS100
CONSTANTS
MATERIAL STEEL_36_KSI ALL
SUPPORTS
1 PINNED
2 FIXED BUT FY MX MZ
LOAD 1 LOADTYPE None TITLE LOAD CASE 1
JOINT LOAD
2 FY -35
LOAD 2 LOADTYPE None TITLE LOAD CASE 2
JOINT LOAD
2 FY -105
LOAD COMB 3 LRFD
1 1.2 2 1.6
LOAD COMB 4 ASD
1 1.0 2 1.0
PERFORM ANALYSIS
PRINT ANALYSIS RESULTS
UNIT INCHES KIP
LOAD LIST 3
PARAMETER 1
CODE AISC UNIFIED 2010
FU 60 ALL
FYLD 35 ALL
LY 180 ALL
METHOD LRFD
TRACK 2 ALL
CHECK CODE ALL
LOAD LIST 4
PARAMETER 2
CODE AISC UNIFIED 2010
FU 60 ALL
FYLD 35 ALL
LY 180 ALL
METHOD ASD
TRACK 2 ALL
CHECK CODE ALL
FINISH
STAAD.Pro Output
STAAD.PRO CODE CHECKING - (AISC-360-10-LRFD) v1.4a
********************************************
ALL UNITS ARE - KIP INCH (UNLESS OTHERWISE Noted)
MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/
FX MY MZ LOCATION
=======================================================================
1 ST PIPS100 (AISC SECTIONS)
PASS Eq. H1-1a 0.961 3
210.00 C 0.00 0.00 0.00
|-----------------------------------------------------------------------|
| SLENDERNESS |
| Actual Slenderness Ratio : 99.349 L/C : 3 |
| Allowable Slenderness Ratio : 200.000 LOC : 0.00 |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS |
| Critical L/C : 3 Ratio : 0.961(PASS) |
| Loc : 0.00 Condition : Eq. H1-1a |
|-----------------------------------------------------------------------|
| DESIGN FORCES |
| Fx: 2.100E+02(C ) Fy: 0.000E+00 Fz: 0.000E+00 |
| Mx: 0.000E+00 My: 0.000E+00 Mz: 0.000E+00 |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES (UNIT: INCH) |
| Azz: 5.750E+00 Ayy: 5.750E+00 Cw: 0.000E+00 |
| Szz: 2.809E+01 Syy: 2.809E+01 |
| Izz: 1.510E+02 Iyy: 1.510E+02 Ix: 3.020E+02 |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES |
| Fyld: 35.000 Fu: 60.000 |
|-----------------------------------------------------------------------|
| Actual Member Length: 360.000 |
| 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 31.62 N/A 91.14 T.B4.1(a)-9 |
| Non-Slender 31.62 N/A 91.14 T.B4.1(a)-9 |
| Flexure : Compact 31.62 58.00 256.86 T.B4.1(b)-20 |
| Compact 31.62 58.00 256.86 T.B4.1(b)-20 |
STAAD SPACE -- PAGE NO. 7
STAAD.PRO CODE CHECKING - (AISC-360-10-LRFD) v1.4a
********************************************
ALL UNITS ARE - KIP INCH (UNLESS OTHERWISE Noted)
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL TENSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Yield 0.00E+00 3.62E+02 0.000 Eq. D2-1 3 0.00 |
| Rupture 0.00E+00 5.18E+02 0.000 Eq. D2-2 3 0.00 |
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL COMPRESSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Maj Buck 2.10E+02 2.19E+02 0.961 Eq. E3-1 3 0.00 |
| Min Buck 2.10E+02 3.19E+02 0.658 Eq. E3-1 3 0.00 |
| Intermediate |
| Results Eff Area KL/r Fcr Fe Pn |
| Maj Buck 1.15E+01 99.35 2.11E+01 2.90E+01 2.43E+02 |
| Min Buck 1.15E+01 49.67 3.08E+01 1.16E+02 3.55E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Local-Z -0.00E+00 1.09E+02 0.000 Eq. G6-1 3 0.00 |
| Local-Y 0.00E+00 1.09E+02 0.000 Eq. G6-1 3 0.00 |
| Intermediate |
| Results Aw Cv Kv h/tw Vn |
| Local-Z 1.15E+01 0.00 0.00 0.00 1.21E+02 |
| Local-Y 1.15E+01 0.00 0.00 0.00 1.21E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR TORSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| 0.00E+00 1.09E+03 0.000 Eq. H3-1 3 0.00 |
| Intermediate Fcr Tn |
| 2.10E+01 1.22E+03 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major -0.00E+00 1.16E+03 0.000 Eq. F8-1 3 0.00 |
| Minor 0.00E+00 1.16E+03 0.000 Eq. F8-1 3 0.00 |
| Intermediate Mn My |
| Major 1.29E+03 0.00E+00 |
| Minor 1.29E+03 0.00E+00 |
STAAD SPACE -- PAGE NO. 8
STAAD.PRO CODE CHECKING - (AISC-360-10-LRFD) v1.4a
********************************************
ALL UNITS ARE - KIP INCH (UNLESS OTHERWISE Noted)
|-----------------------------------------------------------------------|
| CHECK FOR FLEXURE TENS/COMP INTERACTION |
| RATIO CRITERIA L/C LOC |
| Flexure Comp 0.961 Eq. H1-1a 3 0.00 |
| Flexure Tens 0.000 Eq. H1-1b 3 0.00 |
| Intermediate Mcx Mrx Pc |
| Mcy Mry Pr |
| Flexure Comp 1.16E+03 -0.00E+00 2.19E+02 |
| 1.16E+03 0.00E+00 2.10E+02 |
| Flexure Tens 1.16E+03 -0.00E+00 3.62E+02 |
| 1.16E+03 0.00E+00 0.00E+00 |
|-----------------------------------------------------------------------|
66. LOAD LIST 4
67. PARAMETER 2
68. CODE AISC UNIFIED 2010
69. FU 60 ALL
70. FYLD 35 ALL
71. LY 180 ALL
72. METHOD ASD
73. TRACK 2 ALL
74. 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. 9
STAAD.PRO CODE CHECKING - ( AISC-360-10-ASD) v1.4a
********************************************
ALL UNITS ARE - KIP INCH (UNLESS OTHERWISE Noted)
MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/
FX MY MZ LOCATION
=======================================================================
1 ST PIPS100 (AISC SECTIONS)
PASS Eq. H1-1a 0.963 4
140.00 C 0.00 0.00 0.00
|-----------------------------------------------------------------------|
| SLENDERNESS |
| Actual Slenderness Ratio : 99.349 L/C : 4 |
| Allowable Slenderness Ratio : 200.000 LOC : 0.00 |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS |
| Critical L/C : 4 Ratio : 0.963(PASS) |
| Loc : 0.00 Condition : Eq. H1-1a |
|-----------------------------------------------------------------------|
| DESIGN FORCES |
| Fx: 1.400E+02(C ) Fy: 0.000E+00 Fz: 0.000E+00 |
| Mx: 0.000E+00 My: 0.000E+00 Mz: 0.000E+00 |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES (UNIT: INCH) |
| Azz: 5.750E+00 Ayy: 5.750E+00 Cw: 0.000E+00 |
| Szz: 2.809E+01 Syy: 2.809E+01 |
| Izz: 1.510E+02 Iyy: 1.510E+02 Ix: 3.020E+02 |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES |
| Fyld: 35.000 Fu: 60.000 |
|-----------------------------------------------------------------------|
| Actual Member Length: 360.000 |
| 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 31.62 N/A 91.14 T.B4.1(a)-9 |
| Non-Slender 31.62 N/A 91.14 T.B4.1(a)-9 |
| Flexure : Compact 31.62 58.00 256.86 T.B4.1(b)-20 |
| Compact 31.62 58.00 256.86 T.B4.1(b)-20 |
STAAD SPACE -- PAGE NO. 10
STAAD.PRO CODE CHECKING - ( AISC-360-10-ASD) v1.4a
********************************************
ALL UNITS ARE - KIP INCH (UNLESS OTHERWISE Noted)
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL TENSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Yield 0.00E+00 2.41E+02 0.000 Eq. D2-1 4 0.00 |
| Rupture 0.00E+00 3.45E+02 0.000 Eq. D2-2 4 0.00 |
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL COMPRESSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Maj Buck 1.40E+02 1.45E+02 0.963 Eq. E3-1 4 0.00 |
| Min Buck 1.40E+02 2.12E+02 0.659 Eq. E3-1 4 0.00 |
| Intermediate |
| Results Eff Area KL/r Fcr Fe Pn |
| Maj Buck 1.15E+01 99.35 2.11E+01 2.90E+01 2.43E+02 |
| Min Buck 1.15E+01 49.67 3.08E+01 1.16E+02 3.55E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Local-Z -0.00E+00 7.23E+01 0.000 Eq. G6-1 4 0.00 |
| Local-Y 0.00E+00 7.23E+01 0.000 Eq. G6-1 4 0.00 |
| Intermediate |
| Results Aw Cv Kv h/tw Vn |
| Local-Z 1.15E+01 0.00 0.00 0.00 1.21E+02 |
| Local-Y 1.15E+01 0.00 0.00 0.00 1.21E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR TORSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| 0.00E+00 7.28E+02 0.000 Eq. H3-1 4 0.00 |
| Intermediate Fcr Tn |
| 2.10E+01 1.22E+03 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major -0.00E+00 7.73E+02 0.000 Eq. F8-1 4 0.00 |
| Minor 0.00E+00 7.73E+02 0.000 Eq. F8-1 4 0.00 |
| Intermediate Mn My |
| Major 1.29E+03 0.00E+00 |
| Minor 1.29E+03 0.00E+00 |
STAAD SPACE -- PAGE NO. 11
STAAD.PRO CODE CHECKING - ( AISC-360-10-ASD) v1.4a
********************************************
ALL UNITS ARE - KIP INCH (UNLESS OTHERWISE Noted)
|-----------------------------------------------------------------------|
| CHECK FOR FLEXURE TENS/COMP INTERACTION |
| RATIO CRITERIA L/C LOC |
| Flexure Comp 0.963 Eq. H1-1a 4 0.00 |
| Flexure Tens 0.000 Eq. H1-1b 4 0.00 |
| Intermediate Mcx Mrx Pc |
| Mcy Mry Pr |
| Flexure Comp 7.73E+02 -0.00E+00 1.45E+02 |
| 7.73E+02 0.00E+00 1.40E+02 |
| Flexure Tens 7.73E+02 -0.00E+00 2.41E+02 |
| 7.73E+02 0.00E+00 0.00E+00 |
|-----------------------------------------------------------------------|