Expansive soils

[ONENGINEER]

Is there any relationship between the Potential Vertical Rise (PVR) and differential vertical movement(Ym).

Also despite reviewing a number of design documents in the Huston Area, I am still not crttain how they make a decision to choose a slab-on-ground and a slab on piers, based on the soil expandivity. I appreciate if someone can enlighten me about this local practice.

 

[ONENGINEER]

The question was revised. Sorry for the inconveniences as the original question was typed in the last minutes of the night.

Can the PVR be derived from the differential vertical movement(y[sub]m[/sub]). It seems if the slab is a square with dimension e[sub]m[/sub], the y[sub]m[/sub] value should be practically very near to PVR.

Also despite reviewing a number of design documents in the Huston Area, I am still not certain how they make a decision to choose the type of a slab-on-ground (super slab, floating or uniform thickness types) based on the soil propensity for vertical movements.