P Delta Analysis tab
Used to direct STAAD.Pro to perform a second order analysis.
Refer to TR.37.2 P-Delta Analysis Options for additional information.
|Number of Iterations||Specify the number of iterations to be performed. If specified, the program will perform the specified number of iterations whether or not the solution converges.|
|Use Geometric Stiffness (Kg)||
P-Delta analysis including stress stiffening effect of the KG matrix. With this option the global stiffness is adjusted with every iteration.
A regular STAAD.Pro P-Delta Analysis performs a first order linear analysis and obtains a set of joint forces from member/plates based on the large P-Delta effect. These forces are added to the original load vector. A second analysis is then performed on this updated load vector (5 to 10 iterations will usually be sufficient).
In the new P-Delta KG Analysis, that is, with the Kg option selected, the effect of the axial stress after the first analysis is used to modify the stiffness of the member/plates. A second analysis is then performed using the original load vector. Large & small P-Delta effects are always included (1 or 2 iterations will usually be sufficient).
Select this option to include both P-small and large Delta effects (recommended), sometimes referred to as P-δ & P-Δ. Leave this box uncheck to only include the "PlargeDelta" effects (P-Δ only).
Without the Small Delta option (i.e., a default STAAD.Pro P-Delta analysis), STAAD.Pro performs a first order linear analysis and obtains a set of joint forces, from members/plates based on the large P-Delta effect, which are then added to the original load vector. A second analysis is then performed on this updated load vector.
With the Small Delta option selected, both the large & small P-Delta effects are included in calculating the end forces, (5 to 10 iterations will usually be sufficient).
|Print Option||Standard STAAD.Pro analysis print options: