Well, you'd expect it to double at least. Undrained shear strength increases with confining strength / or depth eg. commonly Su is given as 0.1-0.4 * sigmav' or Su = Su(0) + k*z where k can range from 1-10.
By structural engineering logic then I suppose your entire site should be in the process of collapsing since the " Bearing Capacity " is exceeded at 8m depth simply by the in-situ stress ;)
Usually the limits are governed by local practice, conservatism / comfort level, and pragamatic concerns rather than what a formulae will tell you. Most foundation problems are really governed by settlement and differential settlement in reality.
I'm trying to find a reference (preferably with case histories) for expected horizontal displacement ranges of an earth dam during construction as a percentage of height, eg. 0.5% to 1.0% of the height. I have that range (up to ~1.0%) in my head as a rule of thumb some grey haired guy in a...
I guess my first thought is, is there an alternative - could they just shift the electrical tower? Is there an alternative foundation methodology that avoids all this? Personally I'd want to see a better explanation for how the steel casing is meant to protect the pipeline. What depth is the...
The struts / walers cause load re-distribution would be the theoretical explanation for the non-triangular distributions. The origin of them was Terzhagi / Peck / others measurements of loads behind actual walls and finding the measurements were non-triangular, although I think with modern FE...
I don't have a neat mathematical formula for you but yeah usually you ignore the gravel layer in this context and the forces are derived from long term properties of the soil behind it.
Just curious if anyone has been through Colorado School of Mines Underground Construction and Tunnel Engineering program or the University of Illinois Urbana-Champaign online geotechnical programs
Technically it sounds like an interesting project in terms of challenges, there's alot going on. The problem is to do it properly you need to either do something extraordinarily conservative or apply a high level of rigour in investigation and modeling. Likely your client wont want to pay for or...
I guess there are those Terzhagi and Peck apparent earth pressure diagrams for based excavations, are they applicable to your style of design? Eg CFEM 4th edition Section 26.10.3 or Figure 26 in NAVFAC DM7-02 https://web.mst.edu/~rogersda/umrcourses/ge441/DM7_02.pdf
In geotech, you can start out doing nuclear densometer testing, concrete testing, scalas, shear vanes, hand augers, etc. Then after a year or two of that, you can stand behind a drill rig logging core for a year or two. Then you can spend a year doing engineering QA on a construction site. Then...
Per chance is the test to achieve CBR value one that the contractor is doing themselves? Or worse, are they doing something like a DCP or shear vane to CBR correlation and then trying to get you to give them CBR to bearing?
Inferring that's the case, I would be hesitant to trust contractors to...
I used to always recommend not tying a slab-on-grade to the concrete wall but I commonly had structural engineers do the doweling in thing anyway (and would tell me about it) or ignoring us and doing it. So I'm not sure one way or the other. As a geotech, floating it in these circumstances seems...
