Dilatometer info

[eric1037]

I was researching flat dilatometer information and came across this web site:

http://www.marchetti-dmt.it/

It has numerous papers that are downloadable.

 

[BigH]

Thanks - I've seen the site too, in the past. Also do check out Paul Mayne's web site (do a search for him) - prof at GaTech. He's one of the gurus of in situ testing now!

 

[jdonville]

Eric, thanks for the reference.

It reminded me of when I was still based in Chicago, and we used In-Stu Soil Testing (Roger Failmezger) out of Virginia to some work in East Dubuque, IL involving dilatometer testing at discrete intervals, pressuremeter testing at discrete intervals at locations near to the dilatometer test "holes", and piezocone readings at the same locations as the pressuremeter. The company has a rig that (obviously) can do CPT and DMT.

The really cool thing was that the pressuremeter was in-line behind the CPTu - thus minimizing the amount of stress relaxation in the sandy soils that we were sampling. We ended up getting way higher soil modulus and effective friction angle values than were suggested by published correlations with SPT N-values.

We were fortunate that the DOT was open to this sort of "nonstandard" testing.

Jeff

 

[Mccoy]

By the way,
I met Professor Marchetti a couple of times, he is a real gentleman and his work has been supported by Schmertmann himself.
BUT.....
the plots in the Marchetti's website would suggest perfect correlations with geotechnical parameters.
I do wonder if it is really so. Just too good to be true.
I've just been talking with colleaugues who use it regularly, they found the edometric modulus from the dilatometer often yields suspiciously high values for cohesives...
Or maybe are the lab tests which so far have invariably yielded low values???

Do you guys have any direct experience on the reliability of the dilatometer modulus Ed ? Also, it's not clear to me wheter it's measured by the blade membrane (horizontal direction) or by the push resistance (vertical direction).

 

[Mccoy]

By the way, these are the updated prices in my area:

(One Euro = about 1.25 US$)

MCPT = 12 Euro /meter
ECPT = 22 " with piezocone
DTM = 42 "

Clearly, you need a fat budget to consider the dilatometer.