Interpreting SPT and N values
Interpreting SPT and N values
(OP)
I have boring logs on a project which give SPT values and a classification chart for the N values. Some of the SPT values have two numbers, eg. 50/3. I understand this to mean it takes 50 blows for the split spoon to penetrate 3" - is this correct? (I am not a geotechnical engineer!) I also presume that this is very hard material (Yes?) but why would the blow count not continue until the foot penetration was achieved and report the resulting N value (blow vounts per foot)





RE: Interpreting SPT and N values
In any case the spoon was not designed for such hard material
StephenA
RE: Interpreting SPT and N values
Over driving will damage the ring at the front of the spoon.
If the ring is damaged, it can alter the rest of the samoling.
RE: Interpreting SPT and N values