dissipating footing pressure to soil below

[ketanco]

when we dissipate the footing pressure to the soil below, the pressure we take for the bottom of footing level should be

pressure coming from the building - pressure because of excavated material

and then we dissipate this net pressure, which mean the net pressure increase, to the soil below...

right?

sounds straightforward but i saw that at a few different locations they ignored subtracting the excavated soil. it means they omitted this by mistake correct?

 

[MikeMcC215]

Yes, the net pressure increase to be used at bot of ftg has overburden subtrafcted. Only the pressure additional to this will cause increase in stresses in soil layers below.

 

[ketanco]

got it thanks