Topics Covered in This Issue Include s4

SUPERPAVE Digest 127

Topics covered in this issue include:

1) New Provisional Standards for TP-1 by 2) RE: New Provisional Standards for TP-1 by "Logan-Cory, Suzanne" 3) RE: New Provisional Standards for TP-1 by BYRD Matthew 4) RE: New Provisional Standards for TP-1 by [email protected]

 To:  Subject: New Provisional Standards for TP-1  From:  Date: 4 Nov 1998 11:16:43 CST

Is anybody interpreting the new provisional standard for the BBR that plastic sheeting is required? We are currently using a double sided release paper. This works very well. No cleaning is required. We just throw them away.

7.1 of TP-1 is where this is mentioned. Any thoughts? Anybody with a quick response will be appreciated. We have our AASHTO inspection tomorrow. Thanks.

John Dageforde Bituminous Laboratory Nebraska Department of Roads Phone: (402) 479-4774 E-mail: John [email protected]

 To: "'[email protected]'"  Subject: RE: New Provisional Standards for TP-1  From: "Logan-Cory, Suzanne"  Date: Wed, 4 Nov 1998 11:36:06 -0600

The plastic sheeting is required and always has been. We've also tried the release paper. I think it works a lot better than the plastic strips, but it has never been allowed in either the AASHTO or ASTM procedures.

 To: "'[email protected]'"  Subject: RE: New Provisional Standards for TP-1  From: BYRD Matthew  Date: Wed, 4 Nov 1998 11:42:27 -0600 Looks to me like the new 7.1 allows for a thinner plastic sheeting. 0.08mm -0.15mm as opposed to 0.12mm - 0.15mm. The recommendation for laser transparency is the same. I would find some clear transparency paper.

Matthew Byrd <<...>>

 To: [email protected]  Subject: RE: New Provisional Standards for TP-1  From: [email protected]  Date: Wed, 4 Nov 1998 12:01:07 -0600

Thinner transparency sheets tend to curl and bubble at 163C. This is the temperature that I pour at. The outer edges can be exposed to even hotter temperatures during the trimming. My main concern is non-deformation. Not all transparency films will work. Thicker is usually beter in this case. Size has been a big concern. Too small and beam deforms on demolding. Too tall and edges ripple causing deformation of the beam. Not to mention the rippled strips have to be discarded. Well, maybe I will mention it....

What is the release agent on these double release papers? Are they reusable? What is the cost? Our plastic strips cost about $1 a piece. Where can one buy these double release strips?

My advice: Use what the specification calls for.

Kenneth Hobson Associate Engineer OKDOT