I am not sure how to exactly implement it in SimScale but I think you can use elastic support under constraints to do so. In that you can use orthogonal method through which you can constraint the structure with a high elasticity of the spring in certain direction while allowing movement in others.
As I have explained before also. If you want to utilize 2 to 3 varying quantities, then you should move to the formula rather than table. Because table upload only works with 2 quantities. So either you can have z in first column and pressure in second or time in first column and pressure in second, not all of them together. I would recommend to first play with time only and apply two different pressures to two different surfaces at different time span.
For info. on elastic support, please see here: Elastic support - documentation
and validation: Free vibrations on elastic support
Hope this helps.