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Go to 8th Floor →click Overlay
Select Xref drawing as 8th Floor Linked Drawing
Click OK
Now you see 8th Floor plan.
Drawing Slab
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Go to slabs
Click slab edge
Draw 2 slab edges
Slab thickness is 8” at 8th floor but we will draw slab pieces to assign different thickness to slab areas in slab edge as shown below.
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Click Slab piece
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Draw slab piece are in slab edge
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You can select slab pieces by right clicking and selecting in AutoCAD as shown below.
Edit slab edge and slab piece properties such as thickness and clear cover.
Do not forget to click update button to see changes on 3D view.