The A line decides, dont go into looking at make up of clay and silt individually, look at the fines content (i.e. sum of both). For fine grained soils, anything above 50% in US and 35% in UK is a fine grained soil
there can be exceptions but thats a good base to start from
yes, when I say placing the concrete will improve it, I mean that it will be reapplying the pressure that the soil had felt previously (plus a little more maybe). Soil at grade level loosens a little because of the removal of stress.
If you are really concerned, you can also dig a little pot...
The 6inches of soft stuff beneath the beams is a pain in the ass. I would have definitely made them trim it out before concreting. There's nothing you can really do now bar make them break out your foundations but tbh its not worth all that. the upper 0.6inch or so of soil does tend to get a...
there are many different ways of doing it, the old traditional way was just a lumped factor of safety of 3 on your combined shaft and end bearing capacity.
but read any text book on geotechnical or foundation engineering. 30 seconds of google and you would have got your answer
nothing is s'allowed' or 'not allowed', how you interpret a test is up to you and you have to have justification for it. Impossible for anyone else to answer without knowing the back story/context
again not sure, the height H, is just part of the wall. The wall is a mass gravity wall, the mass of the wall needs to be sufficient to resist sliding and over turning
1500ksf is 71MPa compressive strength.
undrained shear strength is half of that , why do you say its only 2.6ksf?
But to try answer your question, you can work our equivialnt mohr coloumb parameters using the Hoek Brown criteria. There is a rock lab app that floats around online that you can...
for % air voids, you need sepcific gravity, water content and dry density. You have all the info, with an assumption of 2.6-2.7 for specific gravity. Grab a text book, have a go, post your answers and then we can review.
yeah somethings not right, two tests on the same sample should not perform like that. There has been some consolidation (and gain of strength) between the two test pressures.
