Depends on the specific purpose. Most of the projects I'm involved in are in areas where the water table is near surface. Typically, I prescribe backfill with cuttings to -3m, then bentonite chips to surface.
In cases where the borehole is collapsing/flowing, I've even grouted to surface...
While the Geotechnical Baseline Report approach is common, I have seen a shift away from that approach in the mining/heavy civil industry. I've been involved with a number of contracts for "earth-moving" where the geotechnical data reports have been provided as part of the contract, but the...
I'd suggest that the geotech's recommendations are reasonable, both from a technical and cost perspective. Any methods to get you deeper compaction (and less settlement) would be very very expensive. I also think the 1.5" over 20' is reasonable as well, assuming we are talking about...
Error checking and "having a feel" for the answer are important. I also make it a habit of doing "peer review". I've always had a couple of colleagues that I can turn to, to do a double check of my design calcs and technical work. I use this especially when I get the gut feel of something...
You have to look at how much you want/need the position, and as Dan suggests, your current "fair market value". As a prospective employee (during my career changes), I've always started with determining my desire to have a particular job, and what I think I am reasonably worth to the company...
Similar to other comments, get a good experienced geotech firm involved to do an appropriate assessment. This is a common problem around rivers/creeks in Alberta (remember a few years ago homes in Edmonton falling into the North Saskatchewan river). I've seen lots of attempts at using physical...
I believe that SlideRuleEra has something on this on his website. Search previous posts - you may find something on this.
Also, please don't double post.
If I can add to f-d's post, depending on the wall geometry and soil backfill conditions, the drain alone may not be sufficient. Often, either granular backfill against the wall, and/or some sort of wall drain system is connected to the drain pipe to ensure no hydrostatic buildup of pore...
As far as I know, conventional slope inclinometers only have an accuracy of 1mm. I use 4mm as my "movement" criteria (just a bit less than GeoPave's criteria). Also, depending on the structure, acceleration is as important as movement. Stress changes will cause strain, and detection of...
I've seen a spreadsheet set up to crank out M-P Analyses, but to simplify it enough to make the spreadsheet useable, it did make a number of assumptions. I would suggest that it will be quite challenging. Certainly it is do-able, and I would suggest digging out the original papers by...
Are you using this material as backfill or borrow? If not, I would think that its in-situ state would be dense enough not to require any compaction - this could be verified with some test holes and investigation (SPT).
Thanks for the comments. Mostly in line with my design philosphy. I am developing (and have) a large database of peak and residual direct shear results, for the various soil units. Certainly, using residual strengths (from direct shear) would be the lower-bound design case. I justify using...
I'm currently developing a design for a large dam founded on thick, heavily overconsolidated, pre-sheared marine clays. The residual strength of the foundation material is very low - experience in the area uses friction angles of 8 to 12 degrees for design.
Our standard practice is to use...
I echo the comments by geotechniqa. Overall, CSSM is not widely used in common geotechnical practice, however, you will find that in specific cases, an understanding of the theories in CSSM will help you understand the fundamental stress-strain soil behaviour. Going back to my grad school...
The data I am using are all residual strength values (i.e. the sample has been sheared, then the test is re-run to get residual values.
The pencil approach is fine (and what I am currently doing), however, I have alot of data, and I would like to automate the process, then review it. Don't get...
