I agree with BigH and fattdad. The moisture content is almost halfway between PL and LL. Considering this and the Su of 200 kPa, you are definitely dealing with overconsolidated soil. My estimate is OCR between 3.5 to 5.5; therefore, what BigH noted above is spot on. However, this all...
The key is better to be placed where you have the highest vertical contact pressure. If the base is considered rigid, under the heel of the footing (back side) may not be the highest vertical pressure (stress reduction due to overturning moment). In this case, under the stem is better. If the...
It is hard for me to answer this as I have not done too many Laboratory Field Vane test.
I prefer the UU tri-axial test to Unconfined Compression Test and lab vane. It is as fast as UCT and even with one sample you can get good results (e.g, multi stage test). However, if you have no choice...
Without knowing all the details and circumstances, it is hard to comment. Generally, if a surcharge (e.g., MSE wall) is added over compressible soil, it should cause downdrag forces. If the drilled shafts are end bearing on the bedrock, the downdrag forces does not come to effect in...
Hi
SPT can be related to shear strength of the clay. There are couple of correlations around in the reference books. However, these correlations are pretty vague. For example, the associate shear strength for SPT values of 4 to 8 is about 25 kPa to 50 kPa and this does not necessary means a...
I really do not recommend designing a pile based on SPT and/or DCPT in clayey soil. This is just not sensible engineering and also may lead to wrong design which is dangerous. Unless, you try to knowingly be over-conservative in the design.
With these low blow count numbers you can do field...
Hi,
You can design cast-in-place concrete piles (caissons) in order to bear the horizontal and overturning moment. I can suggest the Brom’s method for this analysis and design. There have been several threads in regard to this design method. If your design does not result to considerable...
The common interpretation of Ontario Building Code (OBC) is that the reference is not lower base of the foundation and in most cases is the lower level of building (AKA top of foundation). For example, if you have a site with thick soft clay and use pile foundations driven to the bedrock for...
I am not familiar with IBC. However, in most of the codes that I have been dealing with, the site seismic classification is up to the elevation of the lowest building slab. Which means, lowering the footing is not going to change the condition much. For example, in OBC, even if you put all...
tbh64; I am not sure if I understand what you are referring to as “driving force” and “resisting force”. Are you referring to the force which is applied to your stabilizing piers or this is the horizontal internal forces between the slices? I am not familiar with GSTABL software and maybe...
I completely agree with dgillette. If you are looking at third scenario and want to rely upon the strength of the concrete (not just weight), there are a few more separate calculations that need to be completed. In summary, the overall equilibrium of the concrete mat within and outside of the...
The site seismic classification is considered from lowest building slab level (not foundation level). For example, for a building without basement, it is the ground surface.
We you say “a property excavated to 25 m below ground surface”, I get the impression that you are referring to a...
If the cut is there (complete) before the concrete is placed and fully cured, you should not consider the concrete mat.
If the excavation would be completed at the same time that the concrete is placed (not cured), then I agree with dgillette, you can model the concrete as a surcharge...
I agree with you guys. There are some engineers that devalue the geotechnical engineering which I believe is one of the most complicated and difficult branches of civil engineering
