Llessur
Geotechnical
- Feb 5, 2002
- 10
Hi,
Still trying to get to grips with this interpretive report I'm afraid...please excuse my ignorance as I am rather inexperienced in this field. Please don't worry about any disasters which may result from my lack of knowledge as this report will never be used and is purely for my benefit.
I've got all the data for the site - borehole logs, soil lab test results etc and have a few questions which I am hoping someone will be able to help me with...
1) With regards to plotting the plasticity limits graphically - I have the atterberg limits (PL, LL, PI, moisture content) for various depths in each borehole. How do I need to plot this data graphically to be included in an Interpretive report? I have approx 15 readings from each borehole (about 20 boreholes) and do not know whether to plot each borehole seperately or can I somehow include data from all the boreholes on one plot? Also, do I need to plot both PL & LL or can I just plot the PI?
2) I also have data for Undrained Triaxial Tests done on soil samples from the boreholes at various depths. The tests have been conducted at three different confining pressures - 150, 350 & 700 kN/m2 and for each confining pressure an undrained shear stength (Cu - kN/m2) has been calculated. I need to produce a graph of 'Cu vs depth' but when plotting the data, from which confining stress do I take the Cu from?
3) I have plotted boring logs of SPT N value vs depth/level for each of the lithologies encountered on the site but understand that I may need to include a 'Design Line' on the plots. What exactly does this design line represent and how do I plot it?
4) The report is relating to a tunnel being made in clay - I know I have to use the report to make design recommendations but what exactly recommendations would I be looking to comment upon with regards to the above data?
Any light which can be shed on the above would be very much appreciated!
Still trying to get to grips with this interpretive report I'm afraid...please excuse my ignorance as I am rather inexperienced in this field. Please don't worry about any disasters which may result from my lack of knowledge as this report will never be used and is purely for my benefit.
I've got all the data for the site - borehole logs, soil lab test results etc and have a few questions which I am hoping someone will be able to help me with...
1) With regards to plotting the plasticity limits graphically - I have the atterberg limits (PL, LL, PI, moisture content) for various depths in each borehole. How do I need to plot this data graphically to be included in an Interpretive report? I have approx 15 readings from each borehole (about 20 boreholes) and do not know whether to plot each borehole seperately or can I somehow include data from all the boreholes on one plot? Also, do I need to plot both PL & LL or can I just plot the PI?
2) I also have data for Undrained Triaxial Tests done on soil samples from the boreholes at various depths. The tests have been conducted at three different confining pressures - 150, 350 & 700 kN/m2 and for each confining pressure an undrained shear stength (Cu - kN/m2) has been calculated. I need to produce a graph of 'Cu vs depth' but when plotting the data, from which confining stress do I take the Cu from?
3) I have plotted boring logs of SPT N value vs depth/level for each of the lithologies encountered on the site but understand that I may need to include a 'Design Line' on the plots. What exactly does this design line represent and how do I plot it?
4) The report is relating to a tunnel being made in clay - I know I have to use the report to make design recommendations but what exactly recommendations would I be looking to comment upon with regards to the above data?
Any light which can be shed on the above would be very much appreciated!