A Practical Solution for Turfway Road

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A Practical Solution for Turfway Road
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Project Summary

• Turfway Road is a 1.9 mile improvement project
  through a heavily developed urban corridor. It
  widened a congested two-lane rural typical
  section to five-lanes in order to accommodate a
  2020 design year average daily traffic of 34,900.

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Project Summary

• The scope included improvements to the I-71 /
  I-75 interchange. A conventional solution called
  for replacing the 3-span interstate overpass
  bridge to make room for the widening of Turfway
  Road which occupied the center span of the bridge.

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Project Summary

• We proposed soil nail walls to excavate the
  abutment fill slopes under the flanking spans to
  make room for more traffic lanes. To verify the
  solution, we proposed using what was then called
  TRAF-NETSIM (now CORSIM).
• Once we were selected, we had to make it work.

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Project History

• Selected in late 1996
• Plans submitted (after several budgetary stops
  and starts) in the Summer of 2002
• Construction began in the Summer of 2005, and was
  completed late in 2007.

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Project Innovation

• The proposed soil nail walls saved considerable
  time, money and headache.
• Replacing the existing bridge to make room to
  widening Turfway Road would have cost about 10
  million.
• Replacement of the bridge also would have imposed
  severe maintenance-of-traffic constrictions and
  inconvenience on the 150,000 vehicles per day
  traveling the interstate during construction.

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Project Innovation

• Verifying proposed traffic related solutions,
  (number of lanes, turning movement lane location
  and storage length, proposed geometrics and
  design speeds) fell to the use of a relatively
  new tool, CORSIM.
• CORSIM is a traffic simulation program that
  simulates the flow of the design traffic volumes
  and directions through the proposed solutions.

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Project Innovation

• Like a pipe network program simulating the water
  flow, CORSIM simulates traffic flow through a
  roadway network.

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Project Innovation

• CORSIM allowed the team to propose only enough
  pavement to meet project needs, avoiding costs
  and disturbance to adjacent properties.

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Project Implementation

• Implementing the soil nail wall to accommodate
  the solutions verified through CORSIM meant

seeing if this
could be turned into this.
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Project Implementation

• Soil nail walls were proposed because they allow
  top-down excavation and construction of a
  soil-retaining structure.
• This allowed opening the flanking spans of the
  bridge for the additional lanes while maintaining
  the embankment under live traffic above.

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Project Implementation

• Soil nail wall specification is an outcome-based
  process.
• The drawings define the geometry (height, length,
  slope, etc.) and provide the soil properties.
• The vendors employ that information to design the
  walls and submit drawings and calculations for
  review and approval.

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Project Implementation
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Project Implementation

• However, use of the soil nail wall was not a
  panacea. A number of issues had to be addressed
• Safety of traffic split around the existing
  piers.

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Project Implementation

• Feasibility lane configuration around the piers
  under the bridge was verified compliant with
  design speed and interchange capacity.

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Project Implementation

• Compatibility of typical section, including
  elevated walks, with the variation and geometry
  of abutment types was confirmed.

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Project Summary

• The Turfway Road widening has now been completed
  and has been well received by KYTC District 6,
  the City of Florence, KY and the traveling
  public.
• The project was widened from 2-lanes to as many
  as 7-lanes without the need to take a single
  building along this heavily developed corridor.

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Project Summary

• From preconstruction to the final plan
  implementation only eight parking places were
  lost to the commercial developments along the
  project, and a large park and ride facility was
  created in the process.
• We think this project demonstrates the successful
  use of new technologies, in both design and
  construction that can lead to practical and cost
  effective solutions of our transportation
  problems.

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• Please hold questions
• until end of
• both presentations.