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It's to do with excess pore-water pressure. Think of it in terms of the stress path: during an ideal saturation stage, the effective stress would remain constant (i.e. cell pressure minus pore-water pressure is constant), and usually the deviatoric stress would be zero. In contrast, during the...

Monotonic triaxial tests are loaded in one direction only until they reach failure, however that is defined. Cyclic triaxial tests undergo cyclic loading, whereby the direction of loading is reversed, typically multiple times until a defined failure limit is reached. So yes, a monotonic...

The examples cited in the OP didn't seem to me to be 'reinventing the wheel' sort of stuff. Rather, they seemed to be legitimate disagreement within a highly subjective profession. Ultimately the statements indicate differences in judgement and/or preferences, and they at least seem to be...

To be honest, the examples cited in the OP are all fair challenges - and persistently matters of debate amongst geotechnical engineers. This is somewhat inevitable in an imprecise field with still a lot of subjectivity: it is the old adage of asking 3 geotechnical engineers a question and...

If this is a shallow foundation with vertical and lateral loads being applied simultaneously, then don't forget that the response will be 'coupled', i.e. you can't separate the vertical and lateral responses. If this is the case, then a stiffness matrix approach is likely to be more appropriate.

Thanks for sharing. The video was a good summary of the paper and seems logical. I guess one comment to make: conventionally the internal friction angle is calculated from a 'set of three' drained tests (unless you have a stress path device) and the results from multiple 'sets of three' tests...

The point is that the Cc/Cr approach is a simpler approximation. Too often I have seen engineers use a single value of mv.

I don't know why anyone would use the mv approach - you need numerous different values depending on the stress/strain level. With the Cc/Cr approach you just need those two values. Both approaches should give the same answer, so the decision should be about using the simplest of the methods -...

Fugro have a piece of software called GeODin which is good. There is also a program called Holebase which seems okay too. As ever with these things, you obviously need to spend a bit of time creating the logs in the format you want first, but once created, it's obviously much more efficient to...

The shear stress is equal to normal stress multiplied by the tangent friction angle. If you have lower pore pressure (due to positive excess pore pressure during shearing, i.e. contraction), then this will lower the normal stress, and lower the shear stress. The reverse is true for dilation...

The direct shear test is used to obtain friction angle data - either internal friction angle or interface friction angle. Given these are cohesive samples, I'd expect you'd be more interested in the interface friction angles. Contrary to the widespread outrage here, there is nothing inherently...

Hydraulic conductivity (often erroneously referred to as 'permeability' by geotechnical engineers) is notoriously difficult to measure, despite its fundamental importance for many geotechnical analyses. Generally the Kozeny-Carman equation works well, but I seem to recall it falls apart a little...

Whoever wrote that quote in the OP has, at best, not explained themselves clearly or, at worst, doesn't know what they are talking about . The consolidation stress applied to a CU triaxial is supposed to represent the in situ condition! CU triaxials are much more reliable than UU triaxials...

I've been looking at several drilling rate of penetration (ROP) models and noticed that many of them have empirical factors which are undefined in the original publications. This includes Maurer (1962), Galle and Woods (1963), D-exponent (Bingham; Jorden and Shirley; Rehm and McClendon)...

If you've undertaken a consolidation stage (i.e. drained; volumetric change), then why do you have excess pore-water pressure (i.e. undrained)? This is a little worrying. With regard to consolidation time, t50 (and similar) is supposed to represent the time to dissipate 50% (or whatever the...

Do you mean undertaking a suite of static pile load tests (i.e. a destructive test) to confirm the capacity? What exact ASTM standard? As per my previous post, this if this is what was meant, then it is not feasible to undertake due to cost and time constraints, hence asking about...

I'm involved in a project where the client plans on installing bored piles. These have been designed according to the relevant standards for the area they will be installed in, but there is some suggestion that these capacities should be confirmed post-construction. Some static pile load...

Dutch is, well... Dutch! to me, so I don't know what those documents say. However, in the first link I can't see how the formation factor comes up in the equation on page 5. In any case, it looks like you've got some correlations there. I would just suggest that you undertake some tests so you...

Do you mean a pocket penetrometer (PP) test? Or a fall cone? I don't recognise your terminology.

As an aside, if you are looking at a type of foundation where the vertical, horizontal, moment and torsion responses are 'coupled' (e.g. a shallow foundation), then creating a stiffness matrix would be required. Generally for deep foundations such as piles the responses are sufficiently...