Mechanical APDL Structural Analysis Guide

etc.). The same applies to the values retrieved using *GET,Par,ELEM,n,EFOR and

*GET,Par,NODE,n,RF. The element nodal forces (FSUM,PRNLD, and NFORCE com-

mands) are summed prior to the combination of those forces.

4. Other Capabilities:

Many other postprocessing functions, such as mapping results onto a path, transforming results

to different coordinate systems, and load case combinations, are available in POST1. See The

General Postprocessor (POST1) in the Basic Analysis Guide for details.

6.2.5. Running Multiple Spectrum Analyses

When running multiple spectrum analyses, it is possible compute the effects of multiple spectra inde-
pendently, or to compute a velocity and/or an acceleration response in addition to a displacement re-
sponse.

• To compute the effects of multiple spectra independently (for example, for three orthogonal directions
  for which you then combine in a separat e step), repeat St ep 3: Obtain the Spectrum Solution (p. 138). After
  the first spectrum analysis and for each subsequent analysis, you must activate the modeReuseKey on
  the SPOPT command so that the database and the needed files are ready for the new spectrum analysis.

Reminder: The existing Jobname.MCOM file is appended with the additional spectrum analyses.

• To compute a velocity and/or an acceleration response in addition to a displacement response, the mode
  combination can be performed in a separat e solution phase.

In this case, you must save a copy (/COPY) of the Jobname.MCOM file from the spectrum analysis

step. This ensures that the Jobname.MCOM files used for generating the downstream mode combin-

ations use only the mode coefficients from that independent spectra input.

Reminder: The existing Jobname.MCOM file is also overwritten by the additional mode-combination

step(s).

The procedure to run multiple spectrum analyses is as follows:

1. Enter SOLUTION.
   Command(s):/SOLU
   GUI: Main Menu> Solution


2. Define analysis type.
   Command(s):ANTYPE
   GUI: Main Menu> Solution> Analysis Type> New Analysis
   
   
   • Option: New Analysis [ANTYPE]
   
   
   
   

Choose New Analysis.

• Option: Analysis Type [ANTYPE]

Choose analysis type spectrum.

3. Choose one of the mode combination methods.

Release 15.0 - © SAS IP, Inc. All rights reserved. - Contains proprietary and confidential information

Single-Point Response Spectrum (SPRS) Analysis Process