TR.37.9 Imperfection Analysis

This performs a modified linear elastic analysis using Member Imperfection Specifications (See TR.26.6 Member Imperfection Information) defined on beam and column members.

An Imperfection analysis will reflect the secondary effects only if the camber and/or drift is specified in a DEFINE IMPERFECTIONS specification (TR.26.6 Member Imperfection Information). For combination of load cases, with imperfection, use the Repeat Load specification rather than the Load Combination.

General Format

PERFORM IMPERFECTION ANALYSIS (PRINT { LOAD DATA | STATICS CHECK | STATICS LOAD | BOTH | ALL } )

See TR.37.1 Linear Elastic Analysis for details.

Without one of these analysis commands, no analysis will be performed. These ANALYSIS commands can be repeated if multiple analyses are needed at different phases.

Note: Due to the mechanisms used to include control/dependent systems, if the reactions on control nodes are not included in a statics check then an out of balance report may result. This can be avoided by adding a short stiff member from a control node to the support.