Robert Bennett, EI
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Project Details
◦ Design-Build Project Delivery
Method
◦ Twin Structures 1700 feet long each
◦ Spread Footing and Micro-Pile
Foundations
◦ Cast-in-place balanced cantilever
segmental superstructure
◦ Smaller pre-stressed concrete beam
bridge
◦ Total Project Cost:
 $113,000,000.00
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Project Team
◦ Owner:
 Virginia Department of Transportation
◦ Design Build Firm:
 Bizzack Construction LLC – Prime Contractor
 CJ Mahan Const. Co. – Bridge Sub-Contractor
 Stantec - EOR
 Jansen Spaans Engineering Inc – EOR
 VSL, Inc – PT and Form Traveler Supplier
 Doka – Segmental Form Supplier
◦ Inspection & Contract Management:
 Amec Engineering – Quality Control
 AMT Engineering – Quality Assurance
 RS&H – CEI Oversight
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Project Details
◦ Maximum height over Grassy Creek: 265 feet
 Tallest Bridge in Virginia
Longest Span: 489 feet
Width of Each Bridge: 43 feet
Each Bridge carries 2 lanes of traffic
West portion of the project ends at the Kentucky
State Line.
◦ Connector to future developments
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Structure Details
◦ Length–
1700’
◦ Height265’
◦ Longest Span- 489’
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Material Quantities
◦ Concrete–
16,000 C.Y.
◦ Reinforcing Steel2.6 M lbs.
◦ Post-Tensioning Strand- 150 Miles
Micro-Piles
Micro-Piles
Cast-in-Place Balanced
Cantilever Segmental Bridge
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Protections
◦ Plastic PT Duct
◦ CRR Steel
◦ Mechanical Duct
Couplers
◦ Heat Shrink
◦ Epoxy Coated Tie Wire
Concrete
•High Strength 8,000 psi for
superstructure
•Mass Concrete
•Low Permeability Concrete
Max 1,500 coulombs ( A5 Special)
Max 2,500 coulombs ( A4 General)
Corrosion Resistant Rebar
Low Carbon/Chromium
Long-Term Durability
Epoxy Coated Bar Supports
75 ksi tensile strength
Concrete
Approved 75 concrete mix designs
with compressive strengths from
(1500-8000 psi)
Achieved High early strength to
accommodate casting and erection
schedule
Utilized concrete admixtures:
Superplasticizers HRWR,
Entrained-Air, Retarders, and
Micro-silica
Concrete
Concrete
Strength Avg
Approved 75 concrete mix designs
with compressive strengths from
14000
(1500-8000
psi)
Comp. Strength
12000
10000
(Comp.
Achieved High early strength toLog.
Strength)
8000
PSIaccommodate casting and erection
6000
Last 10 Average
schedule
4000
2000
4,000 in 24 hrs
10,200 in 28
days
Utilized concrete admixtures:
0
Superplasticizers
HRWR,
0
10
20
30
Entrained-Air, Retarders,
and
Days
Micro-silica
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Excavation
◦ Over 2.5 Million CY
◦ Cross Section Cut
160’
◦ Day & Night Shifts
Location of Buchanan Co. Virginia
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Massive Transportation Improvement Plan for the
Appalachian Region
Help boost commerce and tourism for the region
460 Connector will connect this region to the
Kentucky border
Site Conditions
Appalachian Mountain Region
400 feet of elevation differential
Unstable terrain
Treacherous in Changing Weather
Conditions
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On-Site Weather Station
Remote Project Location
Buchanan, Dickenson County VA, Pike
County, KY
Population Density: 63 / Sq. Mile
Nearest Town – Grundy, VA
Population: 1,100
30-40 minutes from project
Labor Force
Small Local Labor Force
Lack of Housing for workers
Extra Costs to Contractor
Long Commutes
Communications
Internet Service
Limited Telephone Service
Limited or No Cell Service
Material Deliveries
Concrete Plant on Site
Delivery Service
Careful Planning
No Overnight Deliveries
Segmental Bridge Specifications
Issues Nationwide with Segmental Bridge Durability
Modified Segmental Specifications Developed for this Project
Addition of a Mock up test requirement
Mock up test
Developed Written Specification
Virginia Research Council
C.J. Mahan Constructed & performed grouting
FHWA Participation
Segmental Bridge Specifications
Because of the results of this Mock-up test, specification and
material changes are being made on a national basis!
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Project Webcam
http://oxblue.com/open/bizzack/vdotus460connector