FHWA Resource Center
STRUCTURES TEAM
PRESTRESSED CONCRETE COMMITTEE FOR ECONOMICAL
FABRICATION
MEETING
OCTOBER 31, 2001
HOLIDAY INN
MANASSAS, VIRGINIA
MEETING MINUTES
A. Introductions and Opening Remarks/Approval of Minutes from June
Meeting
Mr. Lou Triandafilou of the FHWA convened the meeting at 9:00am. The
participants were welcomed and asked to give a self introduction. A copy of the
current mailing list was circulated among the attendees and they were asked to
verify the information and make necessary corrections.
Mr. Triandafilou indicated that there will be a Spring 2002 meeting ,
possibly in New Jersey. He also stated that subsequent to the Spring meeting ,
we will probably meet only once a year. Subcommittees will therefore play a more
critical role and need to convene in the interim between full PCEF meetings.
An announcement of the untimely passing of Dino Scalia was made and followed
by a moment of silence. Dino chaired the QA/QC subcommittee and was a very
active member of the group. The Shockey Brothers Group will continue to be
involved in committee activities but who would be attending was not known at
this time. An industry contact is needed to replace Mr. Scalia on both the
committee and the sub-committee on QA. The member listing will be reviewed and a
solicitation of the industry folks will be made.
Another of our industry attendees, Mr. Ernie Acree from Bayshore Concrete
Products Inc., has also retired.
The chair asked that State DOT attendees mark on the address list the name(s)
of the people who would be contacts to receive ballots in the future (preferably
one design and materials person).
Minutes from the June meeting were approved with the following revision, as
distributed to the Committee by email. The last paragraph of Section IV,
Production/ Construction Subcommittee Report should be revised to reflect that
the intent of that group was to draft a viable recommendation that can be used
by all DOT's in their day-to-day prestressed member construction/production
needs. In order to develop this draft, the group will use all available
research, studies, specifications, guidelines and any documented information as
submitted by various DOTs, academia and industry personnel. The group is not
aware of any known prestressed concrete repair procedure that has already been
developed by any organization, that can be used in our region without
considerable reviews, revisions and updating.
B. Subcommittee Status Reports
1. Subcommittee on Production/Construction -- Lalith Galagedera, Chair
Since Lalith was not present at the meeting, Lou discussed the progress of
the sub-committee.
A ballot was sent out relating to issues on crack repairs such as type,
location, length, width etc. The Materials Divisions from PA, VA and WV were the
only ones to respond so far. Responses are still being solicited from the other
States, including Design and Materials Divisions. A specific contact person
needs to be identified from each DOT so that the responses get back to the
subcommittee chairman in a timely fashion.
The purpose of the ballots (and of the PCEF as a whole) was discussed,
particularly regarding the final impacts of adopting guidelines and
specifications, and in what direction we were heading. In the interest of
quality, uniformity and economy, attendees agreed that adoption of items should
be taken to mean that consensus has been reached. It was recognized that States
may still deviate from an approved document and maintain some specific
individual requirements, but ideally these would be minimal. The group also
agreed that the PCEF serves as a useful forum for transferring the latest
technology.
As restated from the June meeting, Hank Bonstedt indicated that a PCI
committee headed by Mr. Ed Wasserman (Tennessee DOT State Bridge Engineer) is
soliciting information from across the country for crack repair criteria. This
information should be useful to this PCEF subcommittee.
2. QA/QC Subcommittee on Materials-Bob Horwhat and Paul Finnerty,
co-Chairmen
Paul and Bob have offered to co-chair this sub-committee in order to make
sure that the guide specification currently being worked on is presented to the
entire committee before the Spring meeting and also to carry on any future work
that the group may work on.
Paul gave an update on the status of the specification and the responses to
the ballots that Dino sent out in August of 2001 which asked for comments on the
3rd draft. To date, WV, DE, NY and DC have not responded. Paul handed out copies
of the 4th draft to these states and will forward copies of blank ballots for
their usage. All responses were requested by the end of December.
As an action item, Paul will supply to Lalith Galagedera, a copy of
Maryland's guidelines for curing times for use with his sub-committee.
3. State DOT Implementation of PCEF Bulb-T Shapes
WV has approved the shapes, and is just beginning in-house task force work to
evaluate implementation.
PA has approved the designs using an 8" web. All producers that are approved
by PADOT have the ability to produce this shape. They are still in the process
of evaluating how to introduce the PCEF shapes into the market, initially with
depths < 66". They could be an alternate to the current adjacent to box
beams. With the bulb-T shape requirement for 16' wide casting beds, the
producers would have to alter their plants. This may take 1 to 1½ years to
resolve.
NY now allows the PCEF shapes to be substituted for the New England bulb-Ts,
so they will rely on the market to dictate what is most economical for the DOT.
Contractors now have the option to redesign beams if the properties are slightly
changed. There is a proposed PCEF shape project scheduled for the Fall of
2002.
VA is currently designing several projects to use the PCEF bulb T shapes.
They have developed standard detail sheets for 9 bulb-Ts with 7" webs and at
least 61" webs. In a meeting with fabricators they learned that shallower beams
with more strands is more economical than deeper beams with fewer strands. The
State will not completely eliminate the AASHTO I girders.
A proposal by Bayshore Concrete Products, Inc. to modify the PCEF bottom
flange shape has not been approved by the Standardization Subcommittee.
MD - Prince George's County has used the shape on 1 of their projects.
DE is still looking for a project application.
NJ is in favor of adopting the design and will a report at the next meeting
as to the status of project evaluation.
4. Standardization Subcommittee - John Martin and Claude Napier,
co-Chairmen
On the subject of steel diaphragms, John Martin handed out Standard XXX for
Alternate Steel Diaphragm details and noted that VA plans to implement it.
NJ is making change to use steel intermediate diaphragms as a primary
standard.
NY will look at it but does not anticipate using it as a standard.
WV already uses steel.
PA will continue to use precast concrete diaphragms.
The Subcommittee had been working on a diaphragm layout sheet but is not
currently pursuing it.
Joe Roche indicated that fabricators are having trouble because of strand and
rebar placement not being shown on shop drawings.
5. Design Parameters Subcommittee - Joseph Nagle, Acting Chairman
Joe was unable to attend the meeting to give an update. He has developed
several issues for his group to focus on, and so far has solicited feedback on
strand pattern types that the PCEF can adopt. We will cover this topic at our
next meeting.
C. High Performance Concrete Update
The states in attendance reported the following:
NJ has one project in the works, using piling supplied by Bayshore Concrete
Products. Also suggested using ASTM C-944 to test the abrasion resistance of
HPC. This component of the HPC definition is being evaluated by FHWA.
PA has not used HPC for beams but is working on various mix designs for decks
on the I-99 project. Hank Bonstedt stated that changes in the fineness modulus
of Type III cement may lead to problems in achieving other HPC values.
NY has been using HPC in bridge decks for about 5 years, and is currently
adding fibers to mixes to prevent deck cracking. They have three projects with
HPC structural shapes, using 0.6" diameter strands. They did experience some
problems with low concrete modulus of elasticity, but are now achieving 30 GPa.
There have also been slight problems with labs being able to run the creep test
at 0.4f'c. There do not seem to be any problems with the remaining parameters.
There are 12-13 superstructure projects scheduled for 2002, again using 0.6"
strand in the shapes.
MD has no new structures on the books at this time.
DE has built four projects using 8000 psi concrete, along with a
performance-based specification. They have also built a concrete sheet piling
project. Durability problems have not been evident at this time.
VA is now routinely using HPC; many decks. one superstructure project using
lightweight HPC prestressed girders.
The use of 0.6" strand seems to be sporadic among the states. Fabricators see
it on only 1 out of about every 40-50 projects. They would like to see its use
standardized among the States, so they can resolve bed capacity issues.
D. Delayed Ettringite Formation Research Update
Dr. Richard Livingston of the FHWA's Turner Fairbank Highway Research Center,
along with the University of Maryland and the MDSHA are involved in a research
project to study the possible damage from ettringite formation on Maryland's
bridge structures. At the June meeting in Pittsburgh, he made a presentation
before the committee at which time he solicited the possibility of a pooled fund
study by the other states.
Paul Finnerty gave an update of the progress of the study and posed the
question again before the committee of the pooled fund study. There was no
positive response from the group so the issue seems to be dead at this time.
Note: At a later date, Paul provided a copy of the latest progress report for
the study. Copies are available upon request.
E.New Business
Question by WV. - What states are using Calcium Nitrite in structural shapes?
VA was only respondent indicating that they did. MD and PA has used it in bridge
decks.
Precast Concrete Elements- Do we need to make this issue a part of our
committee? Attendees were agreeable to this, perhaps as a separate
sub-committee. There will be an update at the next meeting by Paul and Bob
Horwhat.
Penalty - For assessing defective prestressed concrete beams, all states
responded that low compressive strength is the only factor used for the purpose
of payment penalties.
Self Compacting Concrete - Put on future agenda as a possible presentation by
an expert in the area.
Meeting adjourned at Noon.