Transcript The DFW Connector Design/Build Experience
DFW Connector Pavement Design and Construction Challenges and Solutions
7 March 2014 2014 Virginia Concrete Paving Conference, Richmond, VA By: Dan Dawood, P.E.
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DFW Connector
Owner: TxDOT D-B Firm: NorthGate Constructors Lead Design: PB Americas Pavement Design: Transtec Cost: Over $1.0 billion Publicly funded CDA: $667 million from public gas taxes, $250 million from ARRA funds, and $107 million from bond proceeds for ROW acquisition.
www.dfwconnector.com
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DFW Connector
Project Length: 8.4-mile initial phase of 14.4-mile project, Existing 12 Lanes Expanding to 24 lanes
CL 2-3 lanes 6-7 lanes 2 lanes 3
DFW Connector Design Tasks
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Thickness design Reinforcement design Temporary pavement design Block-out solutions Terminal joint design Pavement transitions Pavement widenings Gore area design Mix and materials Resilient modulus verification
Pavement Design Tasks 5
CRCP Thickness Design
PCC Thickness Design 10” CRCP for Frontage Roads 13” CRCP for Main lanes, Ramps, and Managed lanes 2.5” HMA Base Layer 12 36” Lime Stabilized Subgrade/Crushed Concrete Base (Effective Plasticity Index Requirements)
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Reinforcement Design
Adopted updated reinforcement standard CRCP (1) -03 Longitudinal Steel 13” CRCP: #6 bar @ 5.5” 10” CRCP: #6 bar @ 7” Transverse steel Varies as a function of pavement width (PW) For 13”: #6 @ 2.5’ for PW < 60 ft up to @1.0’ for PW < 120 ft, CRCP (1) -09 Same Longitudinal Steel as CRCP (1) -03 Transverse steel: #5 @ 48” for PW up to 100 ft
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Optimized PCCP Mix
#57 stone, pea gravel, and natural sand
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Toll Gantry Area Blockouts
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Other Pavement Design Tasks
CRCP Transition Design CRCP to HMA CRCP to existing CRCP CRCP to new CRCP CRCP Thickness Transition Design of Pavement Widenings Drainage Considerations Remaining Life of Existing CRCP Future Rehabilitation Needs ProVAL Analysis - PI vs. IRI
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Accelerated Construction Challenges and Solutions
Construction Schedule: 4 years (2010-2014) Design-Build contracting process
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Accelerated Construction Challenges and Solutions
Keep all lanes open during peak travel times Temporary pavement to shift traffic
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Accelerated Construction Challenges and Solutions
Keep all lanes open during peak travel times Most lane closures scheduled to occur at night (off-peak)
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Accelerated Construction Challenges and Solutions
Varying paving widths: 12’ lanes, 10’-12’ shoulders, 16’-24’ ramps 10’, 12’, 16’, 22’ and 24’ paving widths 10”-13” paving thicknesses Short pours due to MOT and bridge construction EB & WB managed lanes – SH 114
Accelerated Construction Challenges and Solutions
Four new Guntert & Zimmerman pavers S600 – 10’-18’ paving widths S850 – 18’-24’ paving widths
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Accelerated Construction Challenges and Solutions
Four new Guntert & Zimmerman pavers Stringless compatible Mobility – Tracks steer 90° Telescoping End Sections Easy to change widths – 2 hrs 226 lane miles of CRCP (535,000 yd 3 )
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Terex Batch Plant Model S
RexCon Dual Drum 12 yd 3 plant Capacity 600 yph. Typical batch size is 11 yd 3 on flowboy rear discharge trailers 7 yd 3 on tandem dump trucks
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Location of Batch Plant and Yards
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Completed Manage Lanes
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Leica Stringless System
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Leica Stringless System
North bound widening on SH121
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Leica Stringless System
Advantages:
Smoother ride Eliminates man-hours in the field (production and safety).
Eliminates schedule impacts/coordination (stringline setup/removal).
Flexibility Haul route Trucks entrances and exits jump around from area to area (easier set-up)
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