These two quantities are provided on the buckling control data line in the processor input file. This input line is located immediately after the Element Load Multiplier line at the end of the input file.
Printout of the deformation shape can be suppressed as a runtime option by using the "SUPTRN" key word. The "SUPTRN" (and its opposite, "TRANS") keyword overrides the DEFPCH setting on the master control line of the ASCII processor input file.
Centrifugal loads may be included in the buckling analysis using the "CENTRIF" runtime keyword. Note that the axis and location of the rotational axis and the rotation speed must be specified in the processor input file to enable the CENTRIF keyword to function.
Normally, the out-of-plane twisting stiffness for Type-6 elements is set equal to 0.001 times the maximum out-of-plane bending stiffness for that element. If this value is not appropriate, a zero (0.0) out-of-plane twisting stiffness for Type-6 elements can be selected in the Linear Stress Data Input screen at the group level by choosing a value of -2 for the Type-6 plate element twisting moment.
The stress-free reference temperature capability for beams is very flexible. Each beam material can have a separate reference temperature for thermal loading.
Two quantities are output from a SSAP6S buckling analysis: The load multiplier and the normalized buckling mode shape.
The buckling load multiplier may be greater or less than one (1.0) and may have either a positive or a negative sign.
The actual load at buckling for the model is the product of the applied load times the load multiplier. If the load multiplier is negative, the buckling load has the opposite sign of the applied load. For example, a tensile load on a beam model may produce a negative buckling load multiplier indicating that the buckling load is a compressive load.
The analysis will consider all loads to be scaled in unison. A structure loaded by both a thermal and pressure load will consider that both loads exist together and that their ratio is fixed. For example, the program will not determine the pressure buckling load for a structure which is subject to both a varying pressure load and a fixed level of thermal stress. vcj
ALGOR docutechfile:f:\algor\docs\6000_501\ssap6\6015505.htm
