FHWA Resource Center
PCEF Materials and QA/QC Subcommittee
January 27, 2006 @ Maryland State Highway Administration"s District 7 Office
Robert Horwhat, PENNDOT, co-chair
Paul Finnerty, MDSHA, co-chair
Gregory Moore, MDSHA
Paul Ingram, PENNDOT
Waseem Fazal, DelDOT
Larry J. Lundy, VDOT
Gary Schepkev, VDOT
Sammy Searls, WVDOT
Timothy Shaw, Site-Blauvelt, consultant engineers
Mark Hoover, SPI/CABA
Brian Matulewicz, Pennoni Associates
• Approval of August 10, 2005 meeting
o Motion to approve made by Waseem Fazal, seconded by Paul Finnerty. Motion passed.
• Strand Bond Qualification Testing
o Review comments
• No major comments received. Other than Lehigh University, actual testing has not been performed yet by any prestressed company. New Enterprise Stone and Lime anticipates testing in the very near future. Dr. Naito from Lehigh indicated to Bob Horwhat at PENNDOT"s recent concrete conference that he is available for consultation and advice if needed.
o Min. sample size for traditional mix
• The procedure does not currently list the number of HES specimens required. Dr. Naito suggested 5 to start, if std. deviation is reasonably low….if not, increase to 10 samples.
• Test Matrix
o Definition of "small beam"
• At the last meeting, a decision was made that a better of description/definition of "small" beams was needed. Mark Hoover proposed that for the purposes of concrete strength specimen preparation, a small beam be defined as:
• A "small" beam is less than 9 cubic yards.
o For beams requiring 6 to 9 cubic yards of concrete for each beam, require cylinders (6 minimum) for every other beam, or
o For beams less than 6 cubic yards per beam, require cylinders (6 minimum) for every thee beams.
• The definition was brought to a table vote and was accepted.
o Review of submitted QC plan elements
• Many of the QC plan element information were received just prior to the meeting and did not allow sufficient time for assembling and distribution. The group agreed to table the review of this information. Bob Horwhat agreed to assemble the information received for distribution within the next 4-6 weeks. All parties were asked to make electronic copies available to Bob (if they hadn"t already done so) to facilitate preparing the document. The subcommittee agreed that the major elements of the QC guidelines will be distributed at the main session.
o Discussion of SCC use since last meeting
• Recently initiated a 12 month pilot program for use in precast and prestressed concrete plants. FHWA concurred with the program. Data and information to be collected to facilitate final preparation of specifications after the pilot program ends. Extensive mix qualification testing required in advance of use for production. Results will be shared with other DOT"s .
• Waseem indicated that about a 5 month project at Structural Concrete Products (Richmond, VA) involving Double Tees and inverted beams for garages. The producer was highly inconsistent with their QC, batching and air content. The finished product had a significant number of bug holes.
• Bayshore produced a test beam in October. The observed that during production, the SCC looked like it was "rolling" and producing layers. Coring was performed but did not show any cold joints. This mix had a VMA and was not a high fines mix.
• West Virginia
• Does not currently allow SCC for prestressed concrte. Is considering going to 10” slump (8” is max limit now). West Virginia does allow SCC for precast concrete, including box culverts but without any formal qualification procedures (slump is not an acceptance limit for precast).
o NJ DOT conference
• Bob Horwhat indicated that he had been contacted by Lou recently about an upcoming HPC/SCC conference to be held at Rutgers University, Oct 2006. PENNDOT believes they will have enough use/experience by then to participate in a Panel discussion. Others also indicated that they were aware, had been contacted or would like to attend. Details will be shared when they become available.
o Discussion of presentation for QAW
o The group agreed that the following would be presented:
• Updated test frequency matrix
• Final list of QC component elements
• SCC mix qualification and production test methods
• PENNDOT will be receiving another "loaner" Air Void Analyzer from FHWA"s mobile concrete lab during the month of March. PENNDOT had received/utilized an AVA previously, however the results did not correlate well with the companion linear traverse testing done. The results of the previous testing will be forwarded with the meeting minutes. PENNDOT hopes to do some side-by-side testing with the admixture rep"s AVA equipment to see how two AVA"s compare when testing the same sample.
• MDSHA will be hosting their 6th annual concrete workshop on Feb. 28th. Paul Finnerty invited those present to consider sending someone. Cost is $60/person. The workshop will include an SCC update from testing and use in Virginia and a Maryland Bulb-T project.
• Bob Horwhat surveyed the group to see who, if anyone was using corrosion inhibitors in their prestressed concrete mixtures. Bob was asked to survey the group as DCI"s are being considered as a possible means to provide additional corrosion protection to concrete beams. Only NY requires them. VA requires either a DCI or proof that the concrete is low permeability. WV, DE, MD, DC and PA have no such requirement. All agreed that traditional low w/c ratio p/s concrete mixtures are probably sufficiently low in permeability to provide good protection against chloride penetration.
• The group agreed informally that they may consider using the subcommittee forum to address development of a regional QC plan for "precast" concrete elements as well.
The meeting was adjourned at 12:00 PM
PCEF subcommittee file