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4) Next, change the coordinates and rotation for the pasted model in the Paste Coordinates form. You can see a preview of the model if you place the cursor over OK.
5) Click OK and the two models will be merged.
6) Additional models can be added by repeating this process.
Notes:
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2) Copy operation in Model A is by default taken with respect to elevation z=0 while paste operation in Model B is taken by default with respect to the lowest/base level. This is not an issue when base level in both models is at elevation 0 but may cause some discrepancies when base elevation in both models is different than zero. In such case, user may need to apply an appropriate Delta Z to make up this difference to paste objects at the desired elevation in Model B. For example, if base level is at -12ft in both models then enter Delta Z=12ft when pasting objects into Model B so they get pasted at the desired elevation.
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3) Model A and B must have the same database units (click on units > consistent units) to merge the two models without any scaling issue. To fix the scaling issue, go to File > Export > ETABS e2k file, select the same consistent units when prompted then import the e2k file back prior to the copy/paste operations.