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When detailing column bases in structures, there are 3 typical ways of doing it.
1. Cast the column into the footing. You get the rigidity at the base, but you need to ensure the column is vertical during the concrete pour. Not much construction tolerance. This is important if you're doing a 6m high structural column, lightpole or something where it's visible to everyone and if it's excessively out of vertical, people will notice. A 1m high mount pier that only you will see is not so critical. Strength is often fine, it's visual perception of the out of vertical
2. Cast into the footing a bolt cage, and have a baseplate on the column. Put levelling nuts under the baseplate so you can level the column, then non-shrink grout under the baseplate. This gives much tolerance in case the footing pour knocks things out of whack a little. Baseplate thickness and connection to column needs to be sufficient to take the base moment.
3. Same as 2 but use chemical anchors like Ramset Chemsets. More forgiving on the bolt location (ie they can't get knocked during concrete pour), but not as strong as cast-in hold-down bolts. Not to say they won't have enough capacity for a mount pier, just that for structures like portal frame buildings etc where the tension in the bolts is much higher, we prefer cast-in bolts.
All are viable options for the sort of loads, eccentricities, alignments etc tolerable by EQ mounts.
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