V. AISC 360-10 HSST Compact Flange F.6
Verify the available flexural strength of a square HSS flexural member with compact flanges per the AISC 360-10 code.
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 F.6, pp. F30-F31
Details
From reference (2):
Select a square ASTM A500 Grade B HSS beam to span 7.5 ft. The loads are a uniform dead load of 0.145 kip/ft and a uniform live load of 0.435 kip/ft. Limit the live load deflection to L/240. The beam is continuously braced.
Validation
Ultimate moment:
Service moment:
Try a HSS 3 1/2×3 1/2×1/8, which has a plastic section modulus, Zx = 1.93 in3 .
The yield strength, Fy = 46 ksi
Flange compactness: λ = b/t = 27.2
Determine the compact flange ratio limit from Table B4.1b: (Compact)
The available flexural strength:
LRFD:
ASD:
Results
Result Type | Reference | STAAD.Pro | Difference | Comments |
---|---|---|---|---|
ϕbMn (ft·k) [LRFD] | 6.66* | 6.66 | none | |
Mn/Ωb (ft·k) [ASD] | 4.43* | 4.43 | none |
* The reference gives ϕbMn = 6.67 ft·k and Mn/Ωb = 4.44, respectively. The differences are due to either rounding differences.
STAAD.Pro Input
The file C:\Users\Public\Public Documents\STAAD.Pro 2024\Samples \Verification Models\09 Steel Design\US\AISC\AISC 360-10 HSST Compact Flange F.6.STD is typically installed with the program.
STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 18-Feb-19
END JOB INFORMATION
INPUT WIDTH 79
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 7.5 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
END DEFINE MATERIAL
MEMBER PROPERTY AMERICAN
1 TABLE ST HSST3.5X3.5X0.125
CONSTANTS
MATERIAL STEEL ALL
SUPPORTS
1 FIXED BUT MZ
2 FIXED BUT FX MZ
LOAD 1 LOADTYPE None TITLE LOAD CASE 1
MEMBER LOAD
1 UNI GY -0.145
LOAD 2 LOADTYPE None TITLE LOAD CASE 2
MEMBER LOAD
1 UNI GY -0.435
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
FU 8352 ALL
FYLD 6624 ALL
FLX 2 ALL
METHOD LRFD
TRACK 2 ALL
CHECK CODE ALL
LOAD LIST 4
PARAMETER 2
CODE AISC UNIFIED 2010
FU 8352 ALL
FYLD 6624 ALL
FLX 2 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 FEET (UNLESS OTHERWISE Noted)
MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/
FX MY MZ LOCATION
=======================================================================
1 ST HSST3.5X3.5X0.125 (AISC SECTIONS)
PASS Eq. H1-1b 0.919 3
0.00 0.00 -6.12 3.75
|-----------------------------------------------------------------------|
| SLENDERNESS |
| Actual Slenderness Ratio : 65.585 L/C : 3 |
| Allowable Slenderness Ratio : 300.000 LOC : 3.75 |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS |
| Critical L/C : 3 Ratio : 0.919(PASS) |
| Loc : 3.75 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: -6.117E+00 |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES (UNIT: INCH) |
| Azz: 7.313E-01 Ayy: 7.313E-01 Cw: 0.000E+00 |
| Szz: 1.657E+00 Syy: 1.657E+00 |
| Izz: 2.900E+00 Iyy: 2.900E+00 Ix: 4.580E+00 |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES |
| Fyld: 6623.999 Fu: 8351.999 |
|-----------------------------------------------------------------------|
| Actual Member Length: 7.500 |
| 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 0.00 N/A 0.00 N/A |
| Non-Slender 27.17 N/A 35.15 T.B4.1(a)-6 |
| Flexure : Compact 27.17 28.12 35.15 T.B4.1(b)-17 |
| Compact 27.17 60.76 143.12 T.B4.1(b)-19 |
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 6.38E+01 0.000 Eq. D2-1 3 0.00 |
| Rupture -0.00E+00 6.70E+01 0.000 Eq. D2-2 3 0.00 |
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL COMPRESSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Maj Buck 0.00E+00 4.77E+01 0.000 Eq. E3-1 3 0.00 |
| Min Buck 0.00E+00 4.77E+01 0.000 Eq. E3-1 3 0.00 |
| Intermediate |
| Results Eff Area KL/r Fcr Fe Pn |
| Maj Buck 1.07E-02 65.58 4.96E+03 9.58E+03 5.30E+01 |
| Min Buck 1.07E-02 65.58 4.96E+03 9.58E+03 5.30E+01 |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Local-Z -0.00E+00 1.82E+01 0.000 Eq. G2-1 3 0.00 |
| Local-Y -3.26E+00 1.82E+01 0.180 Eq. G2-1 3 7.50 |
| Intermediate |
| Results Aw Cv Kv h/tw Vn |
| Local-Z 5.08E-03 1.00 5.00 27.17 2.02E+01 |
| Local-Y 5.08E-03 1.00 5.00 27.17 2.02E+01 |
|-----------------------------------------------------------------------|
| CHECK FOR TORSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| 0.00E+00 5.49E+00 0.000 Eq. H3-1 3 0.00 |
| Intermediate Fcr Tn |
| 3.97E+03 6.10E+00 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 6.12E+00 6.66E+00 0.919 Eq. F7-1 3 3.75 |
| Minor 0.00E+00 6.66E+00 0.000 Eq. F7-1 3 0.00 |
| Intermediate Mn My |
| Major 7.40E+00 0.00E+00 |
| Minor 7.40E+00 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 0.919 Eq. H1-1b 3 3.75 |
| Flexure Tens 0.919 Eq. H1-1b 3 3.75 |
| Intermediate Mcx Mrx Pc |
| Mcy Mry Pr |
| Flexure Comp 6.66E+00 6.12E+00 4.77E+01 |
| 6.66E+00 0.00E+00 0.00E+00 |
| Flexure Tens 6.66E+00 6.12E+00 6.38E+01 |
| 6.66E+00 0.00E+00 -0.00E+00 |
|-----------------------------------------------------------------------|
48. LOAD LIST 4
49. PARAMETER 2
50. CODE AISC UNIFIED 2010
51. FU 8352 ALL
52. FYLD 6624 ALL
53. FLX 2 ALL
54. METHOD ASD
55. TRACK 2 ALL
56. 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 HSST3.5X3.5X0.125 (AISC SECTIONS)
PASS Eq. H1-1b 0.921 4
0.00 0.00 -4.08 3.75
|-----------------------------------------------------------------------|
| SLENDERNESS |
| Actual Slenderness Ratio : 65.585 L/C : 4 |
| Allowable Slenderness Ratio : 300.000 LOC : 3.75 |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS |
| Critical L/C : 4 Ratio : 0.921(PASS) |
| Loc : 3.75 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: -4.078E+00 |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES (UNIT: INCH) |
| Azz: 7.313E-01 Ayy: 7.313E-01 Cw: 0.000E+00 |
| Szz: 1.657E+00 Syy: 1.657E+00 |
| Izz: 2.900E+00 Iyy: 2.900E+00 Ix: 4.580E+00 |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES |
| Fyld: 6623.999 Fu: 8351.999 |
|-----------------------------------------------------------------------|
| Actual Member Length: 7.500 |
| 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 0.00 N/A 0.00 N/A |
| Non-Slender 27.17 N/A 35.15 T.B4.1(a)-6 |
| Flexure : Compact 27.17 28.12 35.15 T.B4.1(b)-17 |
| Compact 27.17 60.76 143.12 T.B4.1(b)-19 |
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 4.24E+01 0.000 Eq. D2-1 4 0.00 |
| Rupture -0.00E+00 4.47E+01 0.000 Eq. D2-2 4 0.00 |
|-----------------------------------------------------------------------|
| CHECK FOR AXIAL COMPRESSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Maj Buck 0.00E+00 3.18E+01 0.000 Eq. E3-1 4 0.00 |
| Min Buck 0.00E+00 3.18E+01 0.000 Eq. E3-1 4 0.00 |
| Intermediate |
| Results Eff Area KL/r Fcr Fe Pn |
| Maj Buck 1.07E-02 65.58 4.96E+03 9.58E+03 5.30E+01 |
| Min Buck 1.07E-02 65.58 4.96E+03 9.58E+03 5.30E+01 |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Local-Z -0.00E+00 1.21E+01 0.000 Eq. G2-1 4 0.00 |
| Local-Y -2.17E+00 1.21E+01 0.180 Eq. G2-1 4 7.50 |
| Intermediate |
| Results Aw Cv Kv h/tw Vn |
| Local-Z 5.08E-03 1.00 5.00 27.17 2.02E+01 |
| Local-Y 5.08E-03 1.00 5.00 27.17 2.02E+01 |
|-----------------------------------------------------------------------|
| CHECK FOR TORSION |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| 0.00E+00 3.65E+00 0.000 Eq. H3-1 4 0.00 |
| Intermediate Fcr Tn |
| 3.97E+03 6.10E+00 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 4.08E+00 4.43E+00 0.921 Eq. F7-1 4 3.75 |
| Minor 0.00E+00 4.43E+00 0.000 Eq. F7-1 4 0.00 |
| Intermediate Mn My |
| Major 7.40E+00 0.00E+00 |
| Minor 7.40E+00 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 0.921 Eq. H1-1b 4 3.75 |
| Flexure Tens 0.921 Eq. H1-1b 4 3.75 |
| Intermediate Mcx Mrx Pc |
| Mcy Mry Pr |
| Flexure Comp 4.43E+00 4.08E+00 3.18E+01 |
| 4.43E+00 0.00E+00 0.00E+00 |
| Flexure Tens 4.43E+00 4.08E+00 4.24E+01 |
| 4.43E+00 0.00E+00 -0.00E+00 |
|-----------------------------------------------------------------------|