Recent content by geomane

Here is a screenshot from Soil Strength and Slope Stability discussing how to determine undrained shear strength from a CU test. We do this occasionally, if we have the budget. https://files.engineering.com/getfile.aspx?folder=19df9127-88de-4a0b-a61f-4c64f953a754&file=IMG_1545.png

@EireChch, do you ever run into issues with the sample swelling when you use very low consolidation pressures for your first couple of points?

I would like to see the calculated scour depth for your project site. If the surficial soils are scoured, which will remove the overburden from above the base of your footings, your bearing capacity will dramatically decrease. A decrease in your depth to groundwater will also dramatically reduce...

I am going to be providing geotechnical engineering services on the side and am looking into professional liability, or errors and omissions, insurance. Basically, I will only be performing subsurface investigations for residential structures in south Alabama and the Florida panhandle. I have...

The FHWA Geotechnical Site Characterization manual comments on this. I think Holtz and Kovacs does as well.

Are you working in the US?

Research pitcher sampler or Denison sampler

I would recommend setting casing and using mud rotary drilling techniques over hollow stem auger if you are performing SPT borings. You have to keep the hollow stem auger charged with water or drill mud or a quick/boiling condition will develop at the bottom of the borehole. I prefer CPTs for...

@GeoEnvGuy, we are also switching from gINT to open ground.

Ultimate bearing capacity changes with depth, and significantly so in cohesionless soils. Your ultimate gross bearing capacity should be based on an assumed or provided foundation width and depth. If your foundation is constructed deeper than was assumed by the geotech, and puts the failure...

@GeoEnvGuy, I used the strain energy method to determine the preconsolidation pressures. And yes, I plotted the field consolidation curves to get Cc, but my stresses from foundation loads plus insitu will fall below the pre-consolidation pressure.

See attached spreadsheet. Let me know if you have any questions.https://files.engineering.com/getfile.aspx?folder=976b6755-7787-4795-b1a8-24f1a39ba389&file=Consol_Data.xlsx

I just recently read "Geotechnical Engineering in Residual Soils" and based on the statements made in the text, settlement analyses on residual soils are best performed using the coefficient of compressibility (mv). The author is not a fan of working with consolidation test data when plotted on...

Nice work PEinc

Su is affected by moisture content, the effective friction angle is not