When calculating the settlement of a shallow footing on granular soil, what specific soil parameter is primarily used to estimate immediate settlement, and how does it differ from the parameter used for consolidation settlement in clay?

When calculating the immediate settlement of a shallow footing on granular soil, the specific soil parameter primarily used is the Elastic Modulus (often denoted as E or E_s). The Elastic Modulus is a measure of the soil's stiffness or resistance to elastic deformation under stress. Elastic deformation refers to the instantaneous compression of soil particles and air voids without significant expulsion of pore water, and it is largely recoverable if the load is removed. For granular soils like sand and gravel, which have high permeability, water drains very quickly, meaning that almost all settlement occurs immediately ....