A Two-Lift concrete Paving (2LCP) workshop was organized as a part of the Texas Department of Transportation (TxDOT) project 0-6749: Feasibility Study of Two-Lift Concrete Paving (2LCP). This workshop was conducted at the J. J. Pickle Research Campus (PRC), The University of Texas at Austin, Austin, TX on May 23rd, 2013. Dr. Jiong Hu, Texas State University, Research Supervisor, and Dr. David Fowler, The University of Texas at Austin, Co-Research Supervisor, co-chaired the workshop. The workshop offered the option of attending in person or remotely through webinar. Fifty-one attendees were present remotely or in person; 28 in person and 23 persons remotely.

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Two-Lift Concrete Paving
Equipment Perspective
Two-Lift Paving Workshop
University of Texas
23 May 2013

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Two-Lift Concrete Paving
 Two-Lift Paving idea has been around for decades.
 GOMACO did tests to insert dowels into two layer
concrete in early 1990 through about 1996 while working
on development of paver to produce two-lift pavement
with single machine.
 In late 1993 two-lift demonstration for European style
pavement in Detroit using a two paver process.
 European opportunities for single machine two-lift pavers.
 Two-Lift paving using “Smog Eating Concrete” in 2011
 Next up is the Illinois Toll Way project.

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Two-Lift Concrete Paving
 Founder of GOMACO filed the
first patent in January 1976
 Abstract: “A machine for
concurrently laying a dual-layered
cementitious composition on a
base surface with the layers
having different compositions.”
 “EconoCrete” was the
anticipated market.

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Two-Lift Concrete Paving
Machine design included two
paving chambers for the two
different layers of material
planned for the “EconoCrete”
pavement design

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Two-Lift Concrete Paving
Cross section of machine patented at the time
At that time, cost of producing two mix designs for a single project outweighs
savings to be gained by using a lesser quality concrete on the bottom layer

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Two-Lift Concrete Paving
 With eye on European
market, GOMACO
began testing dowel
insertion through two
layers of concrete
placed by single
machine in early 1990s.
 Developed vibration
techniques for IDBI,
bottom course structure
as well as top course.

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving
 1993 two-lift project in Detroit
 Two paver process, and two side delivery
placers because of doweled and jointed
construction
 Surface was complete with high quality
exposed aggregate. Referred to as
European two-lift

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving
European 2-Lift
paving spread
 Conveys top lift
concrete over the
bottom layer paver
 Inserts load transfer
dowels into bottom
layer
 Places and vibrates
top course after
placing dowels

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving
 1997, GOMACO had opportunity to
produce machine for two-lift paving on a
project near Newport, Wales in the U.K.
 CRCP pavement with “Whisper” surface
top course
 Single lane construction, 4-lane highway
 Machine had ability to insert dowels in the
pavement but never used on this project.

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving
 Contractor used continuous wet batch plant
to produce both mix designs
 Job site logistics (including public traffic)
proved to be important consideration on the
project
 Two different types of trucks delivering
materials for top and bottom course helps
prevents mixing loads into the wrong layer

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving
 In 2004 Skanska purchases a 12 meter paver for
producing two-lift pavements in Czech Republic (First
project was paved at just over 10 Meters wide)
 Paver was equipped with IDBI as well as two layer
paving kit.
 First paver ever working in Czech Republic on full 3D
machine control
 Contractor used two separate batch plants to produce
material for two courses

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Two-Lift Concrete Paving
 Trucks delivered material
in three lanes
 Two outside truck lanes
were for delivering
bottom course material
 Middle lane trucks were
delivering the top course
material
 No stringlines present to
hinder truck traffic

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving
2-lift paving w/
“Smog Eating”
Concrete
Missouri DOT
October 2011

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Two-Lift Concrete Paving
Research Project involving MoDOT, CPTech Center, FHWA, & EPA

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Two-Lift Concrete Paving

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Two-Lift Concrete Paving
 Next up will be the Two-lift paving project
being done by the Illinois Toll Way
authority.
 Open House on August 20th and 21st
sponsored by the Illinois Toll Way and
National Concrete Pavement Technology
Center.

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THANK YOU
THE WORLD WIDE LEADER IN
CONCRETE PAVING TECHNOLOGY
Kevin L. Klein
V.P. ENGINEERING / RESEARCH & DEVELOPMENT
GOMACO CORPORATION
121 E. HWY 175, P.O. BOX 151
IDA GROVE, IOWA 51445
Klein@gomaco.com 1-800-831-2320