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Envelopes report only min/max values. Since min/max values in different parts of the model often occur at different time steps, the most realistic results are usually obtained by combining time history cases using the Step-by-Step option shown below.
Result sets apply different code specified design parameters including flexibility factors. In most cases you will want to select Result Set option "All Except Base". The base result set does not include flexibility factors or other design parameters that can affect analysis results.
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