V. AISC 360-05 F.1-3 LTB I Section
References
- Steel Construction Manual, Version 13.0, American Institute of Steel Construction, 2005
- Design Examples, Version 13.0, American Institute of Steel Construction, 2005, Example F1-3, pp.F-11 - F-14
Details
From reference (2):
Verify the strength of the W18×50 beam selected in Example F.1-1a if the beam is braced at the ends and center point rather than continuously braced.
From Example F1-1a (also found in Reference (1) ):
Select an ASTM A992 W-shape beam with a simple span of 35 feet. Limit the member to a maximum nominal depth of 18 in. Limit the live load deflection to L/360. The nominal loads are a uniform dead load of 0.45 kip/ft and a uniform live load of 0.75 kip/ft.
Validation
Refer to reference.
Result Type | Reference | STAAD.Pro | Difference | Comments |
---|---|---|---|---|
ϕbMn (ft·kips) [LRFD] | 288 | 288 | none | |
Mn/Ωb (ft·kips) [ASD] | 192 | 192 | none |
STAAD.Pro Input File
The file C:\Users\Public\Public Documents\STAAD.Pro 2024\Samples \Verification Models\09 Steel Design\US\AISC\AISC 360-05 F.1-3 LTB I Section.STD is typically installed with the program.
STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 25-OCT-12
JOB NAME AISC 360-10 Validation
JOB CLIENT Bentley
JOB NO 7
END JOB INFORMATION
INPUT WIDTH 79
UNIT INCHES KIP
JOINT COORDINATES
1 0 0 0; 2 420 0 0;
MEMBER INCIDENCES
1 1 2;
***************************************************
DEFINE MATERIAL START
ISOTROPIC STEEL
E 29000
POISSON 0.3
DENSITY 0.000283
ALPHA 1.2e-05
DAMP 0.03
TYPE STEEL
STRENGTH FY 36 FU 59 RY 1.5 RT 1.2
END DEFINE MATERIAL
***************************************************
MEMBER PROPERTY AMERICAN
1 TABLE ST W18X50
***************************************************
CONSTANTS
MATERIAL STEEL ALL
***************************************************
SUPPORTS
1 FIXED BUT MZ
2 FIXED BUT FX MZ
***************************************************
LOAD 1 LOADTYPE Dead TITLE LOAD CASE 1
MEMBER LOAD
1 UNI GY -0.0375
**
LOAD 2 LOADTYPE Live TITLE LOAD CASE 2
MEMBER LOAD
1 UNI GY -0.0625
**
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
UNIT FEET KIP
LOAD LIST 3
PARAMETER 1
CODE AISC UNIFIED 2005
METHOD LRFD
FYLD 7200 ALL
FU 65 ALL
CB 1.3 ALL
LX 210 ALL
UNT 17.5 ALL
UNB 17.5 ALL
MAIN 1 ALL
TRACK 2 ALL
CHECK CODE ALL
***************************************************
LOAD LIST 4
PARAMETER 2
CODE AISC UNIFIED 2005
METHOD ASD
FYLD 7200 ALL
FU 9360 ALL
CB 1.3 ALL
LX 210 ALL
UNT 17.5 ALL
UNB 210 ALL
TRACK 2 ALL
CHECK CODE ALL
FINISH
STAAD.Pro Output
STAAD.PRO CODE CHECKING - (AISC-360-05-LRFD) v3.3a
********************************************
ALL UNITS ARE - KIP FEET (UNLESS OTHERWISE Noted)
MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/
FX MY MZ LOCATION
=======================================================================
1 ST W18X50 (AISC SECTIONS)
PASS Eq. H1-1b 0.924 3
0.00 0.00 -266.44 17.50
|-----------------------------------------------------------------------|
| SLENDERNESS |
| Actual Slenderness Ratio : 254.294 L/C : 3 |
| Allowable Slenderness Ratio : 300.000 LOC : 17.50 |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS |
| Critical L/C : 3 Ratio : 0.924(PASS) |
| Loc : 17.50 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: -2.664E+02 |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES (UNIT: INCH) |
| Azz: 8.550E+00 Ayy: 6.390E+00 Cw: 3.046E+03 |
| Szz: 8.889E+01 Syy: 1.069E+01 |
| Izz: 8.000E+02 Iyy: 4.010E+01 Ix: 1.240E+00 |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES |
| Fyld: 7199.999 Fu: 8639.999 |
|-----------------------------------------------------------------------|
| Actual Member Length: 35.000 |
| 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 6.58 N/A 13.49 T.B4.1-3 |
| Slender 45.23 N/A 35.88 T.B4.1-10 |
| Flexure : Compact 6.58 9.15 24.08 T.B4.1-1 |
| Compact 45.23 90.55 137.27 T.B4.1-9 |
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 6.61E+02 0.000 Eq. D2-1 3 0.00 |
| Rupture -0.00E+00 6.61E+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 5.09E+02 0.000 Sec. E1 3 0.00 |
| Min Buck 0.00E+00 5.14E+01 0.000 Eq. E7-1 3 0.00 |
| Flexural |
| Tor Buck 0.00E+00 1.93E+02 0.000 Eq. E7-1 3 0.00 |
| Intermediate |
| Results Eff Area KL/r Fcr Fe Pn |
| Maj Buck 9.88E-02 56.93 5.54E+03 1.27E+04 5.65E+02 |
| Min Buck 1.02E-01 254.29 5.59E+02 6.37E+02 5.71E+01 |
| Flexural Ag Fcr Pn |
| Tor Buck 1.02E-01 2.10E+03 2.14E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Local-Z -0.00E+00 2.31E+02 0.000 Eq. G2-1 3 0.00 |
| Local-Y 3.05E+01 1.92E+02 0.159 Eq. G2-1 3 0.00 |
| Intermediate |
| Results Aw Cv Kv h/tw Vn |
| Local-Z 5.94E-02 1.00 1.20 6.58 2.56E+02 |
| Local-Y 4.44E-02 1.00 0.00 45.23 1.92E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 2.66E+02 3.79E+02 0.703 Eq. F2-1 3 17.50 |
| Minor 0.00E+00 6.23E+01 0.000 Eq. F6-1 3 0.00 |
| Intermediate Mn My |
| Major 4.21E+02 0.00E+00 |
| Minor 6.92E+01 0.00E+00 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-LATERAL TORSIONAL BUCKLING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 2.66E+02 2.88E+02 0.924 Eq. F2-3 3 17.50 |
| Intermediate Mn Me Cb Lp Lr Lb |
| Major 3.20E+02 0.00E+00 1.30 5.83 16.97 17.50 |
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 0.924 Eq. H1-1b 3 17.50 |
| Flexure Tens 0.924 Eq. H1-1b 3 17.50 |
| Intermediate Mcx Mrx Pc |
| Mcy Mry Pr |
| Flexure Comp 2.88E+02 2.66E+02 5.14E+01 |
| 6.23E+01 0.00E+00 0.00E+00 |
| Flexure Tens 2.88E+02 2.66E+02 6.61E+02 |
| 6.23E+01 0.00E+00 -0.00E+00 |
|-----------------------------------------------------------------------|
65. ***************************************************
66. LOAD LIST 4
67. PARAMETER 2
68. CODE AISC UNIFIED 2005
69. METHOD ASD
70. FYLD 7200 ALL
71. FU 9360 ALL
72. CB 1.3 ALL
73. LX 210 ALL
74. UNT 17.5 ALL
75. UNB 210 ALL
76. TRACK 2 ALL
77. CHECK CODE ALL
STEEL DESIGN
STAAD SPACE -- PAGE NO. 6
STAAD.PRO CODE CHECKING - ( AISC-360-05-ASD) v3.3a
********************************************
ALL UNITS ARE - KIP FEET (UNLESS OTHERWISE Noted)
MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/
FX MY MZ LOCATION
=======================================================================
1 ST W18X50 (AISC SECTIONS)
PASS Eq. H1-1b 0.958 4
0.00 0.00 -183.75 17.50
|-----------------------------------------------------------------------|
| SLENDERNESS |
| Actual Slenderness Ratio : 254.294 L/C : 4 |
| Allowable Slenderness Ratio : 300.000 LOC : 17.50 |
|-----------------------------------------------------------------------|
| STRENGTH CHECKS |
| Critical L/C : 4 Ratio : 0.958(PASS) |
| Loc : 17.50 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: -1.838E+02 |
|-----------------------------------------------------------------------|
| SECTION PROPERTIES (UNIT: INCH) |
| Azz: 8.550E+00 Ayy: 6.390E+00 Cw: 3.046E+03 |
| Szz: 8.889E+01 Syy: 1.069E+01 |
| Izz: 8.000E+02 Iyy: 4.010E+01 Ix: 1.240E+00 |
|-----------------------------------------------------------------------|
| MATERIAL PROPERTIES |
| Fyld: 7199.999 Fu: 9359.999 |
|-----------------------------------------------------------------------|
| Actual Member Length: 35.000 |
| 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 6.58 N/A 13.49 T.B4.1-3 |
| Slender 45.23 N/A 35.88 T.B4.1-10 |
| Flexure : Compact 6.58 9.15 24.08 T.B4.1-1 |
| Compact 45.23 90.55 137.27 T.B4.1-9 |
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 4.40E+02 0.000 Eq. D2-1 4 0.00 |
| Rupture -0.00E+00 4.78E+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 3.39E+02 0.000 Sec. E1 4 0.00 |
| Min Buck 0.00E+00 3.42E+01 0.000 Eq. E7-1 4 0.00 |
| Flexural |
| Tor Buck 0.00E+00 1.28E+02 0.000 Eq. E7-1 4 0.00 |
| Intermediate |
| Results Eff Area KL/r Fcr Fe Pn |
| Maj Buck 9.88E-02 56.93 5.54E+03 1.27E+04 5.65E+02 |
| Min Buck 1.02E-01 254.29 5.59E+02 6.37E+02 5.71E+01 |
| Flexural Ag Fcr Pn |
| Tor Buck 1.02E-01 2.10E+03 2.14E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR SHEAR |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Local-Z -0.00E+00 1.54E+02 0.000 Eq. G2-1 4 0.00 |
| Local-Y 2.10E+01 1.28E+02 0.164 Eq. G2-1 4 0.00 |
| Intermediate |
| Results Aw Cv Kv h/tw Vn |
| Local-Z 5.94E-02 1.00 1.20 6.58 2.56E+02 |
| Local-Y 4.44E-02 1.00 0.00 45.23 1.92E+02 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-YIELDING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 1.84E+02 2.52E+02 0.729 Eq. F2-1 4 17.50 |
| Minor 0.00E+00 4.14E+01 0.000 Eq. F6-1 4 0.00 |
| Intermediate Mn My |
| Major 4.21E+02 0.00E+00 |
| Minor 6.92E+01 0.00E+00 |
|-----------------------------------------------------------------------|
| CHECK FOR BENDING-LATERAL TORSIONAL BUCKLING |
| |
| FORCE CAPACITY RATIO CRITERIA L/C LOC |
| Major 1.84E+02 1.92E+02 0.958 Eq. F2-3 4 17.50 |
| Intermediate Mn Me Cb Lp Lr Lb |
| Major 3.20E+02 0.00E+00 1.30 5.83 16.97 17.50 |
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 0.958 Eq. H1-1b 4 17.50 |
| Flexure Tens 0.958 Eq. H1-1b 4 17.50 |
| Intermediate Mcx Mrx Pc |
| Mcy Mry Pr |
| Flexure Comp 1.92E+02 1.84E+02 3.42E+01 |
| 4.14E+01 0.00E+00 0.00E+00 |
| Flexure Tens 1.92E+02 1.84E+02 4.40E+02 |
| 4.14E+01 0.00E+00 -0.00E+00 |
|-----------------------------------------------------------------------|