Increase in allowable soil pressure w/depth

[metljakt]

My state (Wa) just changed over from UBC '97 to IBC 2003. There used to be a provision in UBC '97 for increasing the allowable soil pressure with depth. That seems to have disappeared with the new IBC. Is there anything in ACI that supports this.

 

[BigH]

metljakt - I assume this is allowable bearing pressure based on shear distress (which I would call the allowable bearing capacity) - the more embedment, the greater the allowable bearing pressure (capacity) in shear. Warning, though - keep in mind that allowable bearing pressures (based on settlement constraints) may actually decrease if, by taking your footing deeper, you come closer to a soft compressible clayey/peaty layer. Need always to look at the overall picture.