PCCAS Asphalt Paving Committee Minutes – March 27, 2007
Co-Chair Brad Neitzke began the meeting by requesting that each attendee make their own introductions. Bob Staugaard reminded the group of our antitrust statement and read the pertinent statements. In the future the sign up sheet will have a copy attached and signing the sheet will indicate a persons acceptance of the statement. Brad gave a quick overview of the agenda before starting and requested any addition to the agenda. A couple of items were added.
Shauna Teclemariam gave an update on the work that is ongoing in the Round Robin Task Group. She reviewed the structure of the group as well as the objectives. There was a review of the history of the work for those new to the committee. She continued with an explanation of the “design of the experiment” which was designed to evaluate the reproducibility of the Superpave tests currently in use. Laboratory participants reviewed the data supplied for errors. Some errors were found and needed to be corrected. The Task Group will be meeting in May with the corrected data to finalize the report. Laboratories that did not perform the testing according to random basis were excluded from the analysis. The task group is hoping to complete the final report by this summer. The presentation is included as part of these minutes. There were a few questions and some discussion on the test results.
Click here to view Round Robin presentation (Acrobat, 235 KB).
Pat Turpen gave a short report on the PAV Round Robin work being performed. She recognized the sub-task group members. Pat provided a document that summarized in some detail the issues being researched as well as the procedures that were followed. The conclusion from the data was that the location of the pans in the PAV did not have any influence on the binder test results.
Click here to view PAV summary document (Acrobat, 412 KB).
George Way gave an update on the Asphalt Rubber Task Group meeting from the previous day. The group discussed the work underway in California on asphalt rubber. California will be developing a specification for PG-TR Grades based on the Superpave criteria. There will be a minimum tire rubber content of 10%. Also, there is a criterion that the rubber used must be from tires used and processed in United States. At this time there are only two TR grades, PG 64-28TR and PG 76-22TR, under consideration. The content requirements have not shown to be an issue when trying to meet the performance specifications. California will not allow the use of PPA in the TR products. Documentation on work ongoing in California was provided and is part of these minutes. There was further discussion on the efforts underway in California.
Click here to view PG-TR presentation (Acrobat, 21 KB).
George then moved on to a discussion of the Arizona State University asphalt rubber research and testing program. This program addresses both binder and mixtures. Issues under investigation include the heat island effect, pavement noise and air quality. His presentation is a part of these minutes. Arizona has an end result specification on their gap-graded specification under evaluation. The pay factors include mix properties as well as a compaction factor. They have completed about six projects and there are a number of issues on the compaction effort.
Click here to view ASU research presentation (Acrobat, 671 KB).
John D’Angelo gave a presentation on the development of the Multiple Stress Creep Recovery test and the associated high temperature specification. John described in detail the development of the test and results as well as the basic theory behind the process. This led to the introduction of the non-recoverable compliance value, Jnr. The presentation is a part of these minutes. There were questions and further discussion.
Click here to view Creep Recovery presentation (Acrobat, 930 KB).
John D’Angelo provided the committee with more updates on the status of issues being discussed in the Binder Expert Task Group. He started with an update on work at FHWA on PPA. They have looked at various aspects of the effect of phosphoric acid on different asphalt sources, including the high temperature effect and moisture susceptibility.
Click here to view Phosphoric Acid Modification presentation (Acrobat, 445 KB).
Shauna Tecle-Mariam informed the group that the T-301 Elastic Recovery test is being looked at as the standard procedure for the conference.
Brad Neitzke polled the committee DOT’s on their current mixture design procedures and whether or not they are using the Superpave procedure.
Washington: lowered the fine aggregate angularity requirement and eliminated the flat and elongated requirement for aggregate. Contractors submit the mix designs that are verified by the agency.
Nevada: uses Hveem mix design method and the agency performs the mix designs.
Arizona: about 25% Superpave and about 75% Marshall mix design. The Superpave mix design methodology has been adjusted as follows. Have a 5% target air void requirement. The VMA requirement has an upper limit of 2% over the specified minimum value. The minimum VMA value is 0.5% higher than what is stated in AASHTO M 323. The VFA requirement is not part of the specification. Contractor performs mix designs and the documentation is reviewed by the agency. No verification testing is performed.
FHWA Western Federal Lands: 100% is Superpave except for a few contracts that are continuing from previous years. Contractors perform the mix designs and are verified by agency. Specifications follow AASHTO M 323.
Brad Neitzke indicated that a note has been sent to AASHTO on the need to change T-301 referring to the use of a force adapter in the procedure. AASHTO will have it on their agenda this summer.
Training updates by UC-Berkeley were given by Larry Santucci. The Asphalt Pavement Fundamentals course was well attended this year with a waiting list. This course is planned for next year as well. There have been a few courses taught on specific subjects as requested by agencies. For information on available training, check the website www.techtransfer.berkeley.edu.
Don Powell handed out a chart from Bob Humer of all the grades being used in the PCCAS states. The intention of this chart was not obvious. Bob Staugaard will send a copy of the original chart to Brad who will talk with Bob Humer and prepare the chart for distribution to the committee at the next meeting.
Bob Staugaard reported that the final report on the fatigue study has been submitted to the conference. Bob will send a copy of the report to each member.
Don Powell gave an update on the Producer’s meeting held in February. The dues structure will be kept this year. There will be multiple membership levels including a new level of Associate member. The membership committee will be putting together a list of potential members to be used for recruitment. There will be no Conference meeting this year, but a meeting is being considered for next year.
Pat Turpen is retiring in November and McCall is looking for a replacement.
The next meeting location will be in Vacaville, CA on September 25, 2007.
