V. Single Column P-Delta Analysis
Determine the support forces at the base of the column.
Details
A 12 ft tall column with a fixed base and free end is subject to a 3 kip axial load and a 5 kip lateral load. The section is a W8x10 using steel with a modulus of elasticity of 29,000 ksi.
Validation
Moment at the base including P-Delta
Therefore, the moment is:
M = 5 (144) + 3 (5.57) = 736.72 in·kip
Results
Parameter | Reference | STAAD.Pro | Difference | Comment |
---|---|---|---|---|
Base moment (ft·kip) | 736.72 | 736.72 | none |
STAAD Input
Tip: You can copy and paste this content directly into a .std file to run in STAAD.Pro.
The file C:\Users\Public\Public Documents\STAAD.Pro 2024\Samples \Verification Models\07 Nonlinear Analysis\Single Column P-Delta Analysis.std is typically installed with the program.
STAAD SPACE
START JOB INFORMATION
ENGINEER DATE 22-May-08
END JOB INFORMATION
INPUT WIDTH 79
UNIT FEET KIP
JOINT COORDINATES
1 0 0 0; 2 0 12 0;
MEMBER INCIDENCES
1 1 2;
DEFINE MATERIAL START
ISOTROPIC STEEL
E 4.176e+006
POISSON 0.3
DENSITY 0.489024
ALPHA 6.5e-006
DAMP 0.03
END DEFINE MATERIAL
SET SHEAR
MEMBER PROPERTY AMERICAN
1 TABLE ST W8X10
CONSTANTS
MATERIAL STEEL ALL
SUPPORTS
1 FIXED
PRINT MEMBER PROPERTIES ALL
LOAD 1 LOADTYPE None TITLE LOAD CASE 1
JOINT LOAD
2 FX 5
LOAD 2 LOADTYPE None TITLE LOAD CASE 1
JOINT LOAD
2 FY -3
PERFORM ANALYSIS PRINT STATICS CHECK
CHANGE
LOAD 3 LOADTYPE None VERTICAL
REPEAT LOAD
1 1.0 2 1.0
PDELTA ANALYSIS LARGEDELTA PRINT STATICS CHECK
unit kips inches
PRINT JOINT DISPLACEMENTS ALL
PRINT MEMBER FORCES
FINISH
STAAD Output
MEMBER END FORCES STRUCTURE TYPE = SPACE
-----------------
ALL UNITS ARE -- KIPS INCH (LOCAL )
MEMBER LOAD JT AXIAL SHEAR-Y SHEAR-Z TORSION MOM-Y MOM-Z
1 3 1 3.00 5.12 0.00 0.00 0.00 736.72
2 -3.00 -5.12 0.00 0.00 0.00 0.00
************** END OF LATEST ANALYSIS RESULT **************