SUPERPAVE Digest 450
Topics covered in this issue include:
2) Segregation in Asphalt Pavements and Laser Profilographs by "Geoff Rowe"
To:
Sincerely
Geoffrey M. Rowe ______Abatech, Inc. 73 Old Dublin Pike, #312 Doylestown, PA 18901
Tel: 1 (267) 880-1295 Fax: 1 (561) 679-2464 Mobile: 1 (267) 251-1976 http://www.abatech.com http://www.asphalt-technology.com
To: [email protected] Subject: RE: Segregation in Asphalt Pavements and Laser Profilographs From: "Kenneth Hobson"
Kansas uses a Nuclear Density Gauge for segregation identification and quantification. We will most likely adopt their methods and specifications to a large extent. This falls right in line with responses to my earlier post about longitudinal joint densification which Mr. Rand of the TX DOT kindly provided specifications and test methods. They use a nuclear density gauge. It's nice to have good neighbors that think as I do....
Naturally, permeability problems may exist when one gets into the segregation issues. NCAT and others have done some work in the area. It guess it comes down to a destructive or non- destructive testing regime. I for one, will always choose the non-destructive methods when applicable. With that said, the CoreLok (http://www.instrotek.com ) may prove useful for a permeability index on roadway cores and lab compacted specimens. I am gathering some small amounts of laboratory testing data to examine it's potential. We've done some laboratory permeability tests for research purposes using a commercial permeameter similiar to FL DOT's permeameter. We have a commercial prototype field permeameter but haven't been able to use it on the cold pavements to date (doesn't seal).
Kenneth Hobson [email protected] OK DOT - Bituminous Branch
SUPERPAVE Digest 451
Topics covered in this issue include:
1) Re: Segregation in Asphalt Pavements and Laser Profilographs by [email protected] 2) Re: Segregation in Asphalt Pavements and Laser Profilographs by "Dale Rand" [email protected]
To: [email protected]
Subject: Re: Segregation in Asphalt Pavements and Laser Profilographs
From: [email protected]
Date: Thu, 1 Mar 2001 09:06:59 +0100
In medicin production, segregation is also a problem. In Nature, vol. 386, 27 March 1997, a short article, by Jay Fineberg (Racah Institute of Physics, The Hebrew University of Jerusalem), can be found.
Ronald Vennix Ballast Nedam Infra Contracting Amstelveen, The Netherlands To:
Subject: Re: Segregation in Asphalt Pavements and Laser Profilographs
From: "Dale Rand"
Date: Thu, 01 Mar 2001 14:02:57 -0600 In Texas, we run segregation profiles using nuclear density gauges. We copied this method from the Kansas DOT. Washington DOT is doing this also. We have it as a specification requirement and we have a standard test procedure. It basically entails taking nuclear gauge readings every 5 foot over a 50 foot section. We look at the differential density. It does not work perfectly but it is an objective measure and we have found greatly reduced segregation on the projects where we have used this procedure. If you would like more details let me know or give me a call.
Dale A. Rand, P.E. Bituminous Branch Director TxDOT - Construction Division Phone: 512.232.1903 Fax: 512.232.1939 Email: [email protected] >>> [email protected] 02/28/01 09:33AM >>> We are performing a study on the occurrence of segregation in asphalt pavement structures and hope to be able to define areas using laser or other technology. In particular we are looking at laser profilographs. I would be of great help if any members of the group could point us at existing work or work ongoing by other groups.
Sincerely
Geoffrey M. Rowe ______Abatech, Inc. 73 Old Dublin Pike, #312 Doylestown, PA 18901
Tel: 1 (267) 880-1295 Fax: 1 (561) 679-2464 Mobile: 1 (267) 251-1976 http://www.abatech.com http://www.asphalt-technology.com