In some cases unification between beams and slabs seems to be inconsistent. In this example note that he column highlighted in red is the original sample and shows the line between the beam and floor edge, it appears that in this case where the edges meet with empty space the calculation that takes place has assumed a line for this beam. The one in green shows how once the column is moved down so the beams meet without a void both unify as expected.
By referencing the floor below (highlighted) the voids are filled and the unification process is able to calculate more easily and consistently showing the expected results:
In some cases changing the value of the MS_VISEDGE_DEFAULTS variable operator 'OcclusionTolerance' may have an effect, however we have found the default value of '0.001 Millimeters' is effective in most cases (including where imperial datasets are in use, the calculations use the underlying numbers, the unit is a guide for humans).
See help topic "Unification Glue Settings and Variables" and this blog post for details of Unification Glue behaviour, variables and options. Note: tfunifiers.exe is a multi-threaded process and will benefit from at least 8Gb RAM.
The key-in 'MDL COMMAND DVREFRESH' can be used to refresh DVs if required.