How to modelate SOIL with springs?

[sepultura]

Which parameters of the soil I must to know to modelate it with springs in the ETABS?
Could you explain me?

 

[Murali27]

Sepultura

Soil springs - Structure directly on soil: Then, Subgrade modulus of soil.

-Murali

 

[DENSAL55]

It's same as when you calculate a beam on elastical supports, you represent soil by coefficient of reaction.
Soil - loose k=0.1-0.5 kg/cm3
- medium dense k=0.5-5
- dense k=5-10
- compact k=10-20
- hard k=20-100
you select joints at base then assign->point spring->kx ,ky,kz...etc.
You must add your fondations as a shell model (slab) the joint correspond to shell mesh.
i hope this help.

 

[sepultura]

Is there any relation between coefficient of reaction (kg/cm3) of the soil and resistance soil support (kg/cm2)?

 

[DENSAL55]

Yes there is a relation between coeficient of reaction and resistance of soil p=-k*y
where y is the displacement
p is the pression on the soil
k is the coefficient of reaction.