LATPRM, STRMETH

Bulk Data Entry This parameter controls the Stress Constraint method (LATSTR on the LATTICE continuation line) for the second phase of Lattice Optimization.

Definitions

Parameter Values Description
STRMETH <PNORM, FSD>
PNORM (Default)
The Stress-Norm method is used for the calculation of the stress response that is constrained for tapered beam elements.
FSD
The alternative method is used for the calculation of the stress response that is constrained for tapered beam elements.

Comments

  1. FSD is a heuristic technique and may not always lead to feasible designs compared to PNORM. If you encounter an infeasible design with FSD, then it is recommended to try ASSIGN, UPDATE to use the property file to update the properties of the <filename>_lattice.fem model and use DESVARG (with INIT field set to ANALYSIS). Then you can rerun the <filename>_lattice.fem model with the PNORM method.
  2. Computational speedup of FSD can be compromised if there are a non-negligible number of responses different from stress responses on the lattice beams.