Perform Buckling Analysis tab

Used to instruct STAAD.Pro to perform a buckling analysis.

Refer to TR.37.4 Buckling Analysis for additional information.

Setting

Description

Iterative method

When this option is selected, the program will perform a P-Delta analysis including Kg Stiffening (geometric stiffness of members & plates) due to large & small P-Delta effects. If a non-singular stiffness matrix can be created, then buckling has not occurred. Then the load is increased from the last increment repeatedly until buckling does occur. Then the load is decreased halfway back to the prior increment. This bounds the buckling factor between the last 2 increments. Then STAAD.Pro proceeds to halve the interval until either the change between increments is 0.1% of each other, or the specified number of increments has been exceeded. The resulting factor is reported in the output file. The buckling deformed shape is simply the deformed shape from a static analysis with the near buckling load applied. This could appear more like a crushing, small displacement shape rather than a buckling mode shape. At least 15 iterations are recommended. Buckling will be applied to all primary cases.

Setting	Description
Number of Iterations	Maximum number of iterations. Fifteen is recommended. Note: This parameter is only used for the iterative method. It is ignored for the eigen method.

Eigen method

This buckling method may only be used if an Advanced Analysis license is available. When using the Advanced Solver, the corresponding "buckling modes" are included in the output file.

Print Option

Standard STAAD.Pro analysis print options:

Setting	Description
No Print	No analysis results will be printed to the output file.
Load Data	Prints all the load data.
Statics Check	Provides a summation of the applied loads and support reactions as well as a summation of moments of the loads and reactions taken around the origin.
Statics Load	Prints everything that Statics Check does, plus a summation of all internal and external forces at each joint. This option potentially generates a large volume of output. Note: Since `PRINT STATIC LOAD` generates voluminous output, the printing of summation of internal and external forces at each joint is done for structures which have less than 1,000 joints. If the structure has 1,000 joints or more, this printing will be skipped.
Mode Shapes	Prints mode shape values at the joints for all calculated mode shapes.
Both	This option is equivalent to the Load Data plus Statics Check options.
All	This option is equivalent to the Load Data plus Statics Check.