Electrical Density Gauge

[tumbleleaves]

Does anyone know anything about these things?

1) What is the history, how long have they been around?
2) Have you used them and what do you think?

Would love to get rid of the nuclear gauge. Is this an alternative?

Currently HMA compaction (QA) is done via cores. So it appears that we could do the remaining compaction tests (QA) with an EDG?

 

[PSlem]

Durham Geo came out with this one about 5 years ago. Initial work was by a Purdue prof.

http://www.durhamgeo.com/testing/soils/compaction-mdi.html

 

[tumbleleaves]

Pselm, have you used it? We are looking for something to use on roadway projects. On larger projects and as much as possible we hire consultants to do the QA work.

So I would really like to replace the Nuke gauge and get something that didn't require so much monitoring/certification. Especially since our lab is not used regularly enough (IMHO) to justify the nuke gauge.

 

[PSlem]

We do so little density we use sand cones. Durham Geo gave a speech at our geotech dinner and it seemed a good tool. Call Rudy at Durham. He should be able to put you in touch with a customer.

 

[TDAA]

I have not used one.

I would also check with the controlling agencies on the road projects that you want to use it on (city/county/DOT). Sometimes you can run into those people that only allow exactly what is in their standards, because there is fear of the unknown.

 

[tumbleleaves]

TDAA: We are the agency. I assume we will have to do a certain number of sand cones to assure the equipment is operating properly.

Based on the responses, it doesn't sound like these are used much in practice (or I'm posting in the wrong forum?).

I will likely contact the state DOT, to see if they have an "expert" that will venture an opinion. I'm hesitant about going to the manufacturer for a reference, I certainly wouldn't expect to get an unbiased random reference from the manufacturer.

Engineers are becoming more like lawyers, never say anything unless pressed, then make it as vague as possible and apply numerous caveats. I like that we can post here anonymously--a better sampling method.

 

[TDAA]

You might want to ask the manufacturer anyway, and ask their reference if they know of anyone else in the area using them. Perhaps you can find a couple different users that way.

Unfortunately, my experience with "State Experts" has been that I have been told "If its not in the book, you can't use it."

Take a look at this link to the Transportation Research Board:

http://rip.trb.org/browse/dproject.asp?n=25525

They have contacts for the Delaware DOT that are apparently studying this gauge as a suitable alternative. If you contact them, please clue us in on what they might have to say.

 

[Ron]

Keep in mind that whatever method you ultimately use, you need to correlate that to core densities.