Can you explain a floating pier? I can't find a design for it.
So ideally what you do is build a floor that attaches to the walls using vibration isolators (the big wire rope ones) and you put a big weight in the bottom of the floor placed so that it more or less counterbalances the weight of the telescope plus pier. The pier bolts to this floor. Then you build the walking floor over that floor, but separated. What you want to achieve in terms of engineering is lateral and vertical compliance with no tipping, hence the weight at the bottom.
It might turn out however that a normal concrete construction method would work fine at your location, soil condition, and wind loading. Are you familiar with this formless construction method using foam blocks? They are called ICF Insulated Concrete Forms. Might be worth considering. Are there any problems with ground transmitted vibrations now? Is there a high wind load on the (proposed) building?