Net Allowable Bearing Pressure 2

[mijowe]

It is common for geotechnical reports to list Net Allowable Bearing Pressure for a recommendation for building foundations. When using these recommendations for standard site retaining walls, would an increase in the bearing pressure be acceptable? ie increase the bearing pressure by the depth of the overburden soil over the toe?

 

[pelelo]

I think prior to providing the net allowable bearing capacity, the geotechnical engineer knew where exactly the foundation of the wall was going to be built. Based on that he provides his net bearing capacity recommendations.

If you want to increase the net bearing capacity because the depth of the wall will be deeper than originally, I recommend to get in touch with the geotechnical engineer about that.

 

[EireChch]

If you add the overburden stress to the NABP, you are not increasing it. You are then using the gross allowable bearing pressure (or just the allowable bearing pressure.

The difference between gross and net is not well understood it seems, there is also a lot of ambiguity around terminology when it comes to bearing capacity.

I would always include an equation which clearly shows what is meant by NABP.