V. AISC LRFD - Wide Flange Flexural Strength 1
To determine the design flexural strength of an ASTM A992 W18X40 bent about its strong axis on a 35-ft span with a uniformly distributed load.
Reference
Hand calculation using the following reference:
AISC Load Factor Resistance Design, 3rd Edition, Example 5.1, Case (a), page 5-12.
Details
The beam is braced such that Lb = 2 ft. The deflection at mid-span due to a uniformly distributed service load of 1 kip/ft is also to be calculated.
Fy = 50 ksi |
Length = 35 ft |
Results
Result Type | Reference | STAAD.Pro | Difference | Comments |
---|---|---|---|---|
Design flexural strength, ϕbMn (in·kips) | 3,528 |
3,528 |
none | |
Deflection (in) | 1.90 | 1.8918 | negligible |
STAAD.Pro Input
The file C:\Users\Public\Public Documents\STAAD.Pro 2023\Samples \Verification Models\09 Steel Design\US\AISC\AISC LRFD - Wide Flange Flexural Strength 1.STD is typically installed with the program.
STAAD SPACE BENDING CAPACITY PER AISC LRFD 3RD ED
START JOB INFORMATION
ENGINEER DATE 23-Sep-18
END JOB INFORMATION
*
* EXAMPLE PROBLEM 5.1, CASE (A), PAGE 5-12, AISC LRFD 3RD ED.
* CAPACITY (MNZ) SHOULD BE ABOUT 294 KIP-FT
*
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 35 0 0;
MEMBER INCIDENCES
1 1 2;
MEMBER PROPERTY AMERICAN
1 TABLE ST W18X40
UNIT FEET KIP
DEFINE MATERIAL START
ISOTROPIC MATERIAL1
E 4.176e+06
POISSON 0.3
END DEFINE MATERIAL
UNIT FEET KIP
CONSTANTS
MATERIAL MATERIAL1 ALL
SUPPORTS
1 PINNED
2 FIXED BUT MZ
LOAD 1
MEMBER LOAD
1 UNI GY -1
LOAD COMBINATION 2
1 1.8
PERFORM ANALYSIS
LOAD LIST 1
SECTION 0.5 ALL
PRINT SECTION DISPL
LOAD LIST 2
UNIT FEET KIP
PARAMETER 1
CODE LRFD
MAIN 1 ALL
FYLD 7200 ALL
UNT 2 ALL
TRACK 1 ALL
CHECK CODE ALL
FINISH
STAAD.Pro Output
SECTION DISPL BENDING CAPACITY PER AISC LRFD 3RD ED -- PAGE NO. 3 MEMBER SECTION DISPLACEMENTS ---------------------------- UNITS ARE - INCH MEMB LOAD GLOBAL X,Y,Z DISPL FROM START TO END JOINTS AT 1/12TH PTS 1 1 0.0000 0.0000 0.0000 0.0000 -0.4973 0.0000 0.0000 -0.9571 0.0000 0.0000 -1.3475 0.0000 0.0000 -1.6441 0.0000 0.0000 -1.8290 0.0000 0.0000 -1.8918 0.0000 0.0000 -1.8290 0.0000 0.0000 -1.6441 0.0000 0.0000 -1.3475 0.0000 0.0000 -0.9571 0.0000 0.0000 -0.4973 0.0000 0.0000 0.0000 0.0000 MAX LOCAL DISP = 1.89185 AT 210.00 LOAD 1 L/DISP= 222 ************ END OF SECT DISPL RESULTS *********** 37. LOAD LIST 2 38. UNIT FEET KIP 39. PARAMETER 1 40. CODE LRFD 41. MAIN 1 ALL 42. FYLD 7200 ALL 43. UNT 2 ALL 44. TRACK 1 ALL 45. CHECK CODE ALL STEEL DESIGN BENDING CAPACITY PER AISC LRFD 3RD ED -- PAGE NO. 4 STAAD.Pro CODE CHECKING - (LRFD 3RD EDITION) v1.0 *********************** ALL UNITS ARE - KIP FEET (UNLESS OTHERWISE Noted) MEMBER TABLE RESULT/ CRITICAL COND/ RATIO/ LOADING/ FX MY MZ LOCATION ======================================================================= 1 ST W18X40 (AISC SECTIONS) PASS LRFD-H1-1B-C 0.938 2 0.00 C 0.00 -275.62 17.50 +---------------------------------------------------------------------+ | DESIGN STRENGTHS FOR MEMBER 1 UNITS - KIP IN | | PNC= 23.10 PNT= 531.00 MNZ= 3528.00 MNY= 428.32 VN= 152.24 | +---------------------------------------------------------------------+