Preliminary bearing capacity 1

[nagatalluri]

Is there a way to estimate the preliminary bearing capacity from SPT blow count. I am looking at a soil profile where the bearing soil is Silty Sand with blow count 7. Below the silty sand layer there is an stiff sandstone/IGM material with blow counts in excessive of 50.

Are there any charts available, please let me know

Thanks
NT

 

[nagatalluri]

Oldest guy:

Thanks for the settlement evaluation using the bearing capacity index.

Let's say the soil profile has both sands/silty sands/clays.

Sands/silty sands are going to undergo immediate settlement where as clays have time dependent consolidation settlement.

How do we determine/differentiate the settlement in this case?

For 2" allowable settlement criteria, how do we check and combine the immediate vs consolidation settlement?

Thanks
NT

 

[oldestguy]

Remember the use of this on clays has shown to be light with respect to long term by about 40 percent average. If you set up a spread sheet with each foot or other unit calculated, you may want to adjust the clay part up some in value of computed settlement in that layer. Again, don't expect precise accuracy when input is so rough.