S51_US 171 at LA 8 Roundabout - Before and After Safety and Operations_LTC2013

7/29/2019 S51_US 171 at LA 8 Roundabout - Before and After Safety and Operations_LTC2013

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Roundabout Construction

SP 373-01-0020

LA 8 / US 171 Roundabout

Leesville, LA

Vernon Parish


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What this presentation covers

Recognition for District 08 Design and Traffic

Sections

Difference between a circle and a roundabout

Why did DOTD elect to construct theRoundabout?

Public Meeting and Public Perceptions

Barrier Curb and Gutter Modifications

Challenges for Sequences of Construction

Time Constraints

General Public Comments andEnd Results


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Recognition for District 08 Design and Traffic Sections

Dale Craig District 08 Traffic Section

Recommended roundabout design and spearheaded

the project to the design phase

Jason Rachal District 08 Design Section

The overall success for this project is greatly

attributed to the project plans developed by Jason

Rachal

David Backstedt - District 08 Traffic Engineer

David meet with me on the project site on numerous occasions

in order to monitor the traffic flow after each constructionsequence change.


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Circle or Roundabout ?

Circle

Area = r2Roundabout


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Why did DOTD elect to construct theRoundabout?

Permit request for

access to a proposed

Market Basket grocery

store

Traffic Study and

Evaluation

Buy-in from DOTD,

Market Basket and City

of Leesville

Proposed

Market

Basket

location


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Public Meeting andPublic Perceptions


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Public Meeting and Public Perceptions


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Public MeetingPublic Perceptions


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Class M Concrete Mix Design

ModificationsRecommend not using Grade A (Size 57) coarse aggregate (100%

passing the 1 US Sieve)

Recommend changing mix design to max size Grade P (Size 67)

coarse aggregate (100% passing the US Sieve)

Barrier Curb and GutterModifications

Installed continuous

steel reinforcement in

the barrier curb section


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Installed Bolster Blocks behind sharp angled corners of

curb section

Barrier Curb and GutterModifications


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Time Constraints

Project Letting Date: July 21, 2010

Work Order Date: September 24, 2010

Roundabout Opening Date: August 1, 2011

Market Basket Grand Opening Date: August 4, 2011

Governors Ribbon Cutting Date: August 5, 2011


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Sequence of Construction - Phase I


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Temporary Traffic Signals

installed at intersection of LA

8 and US 171

Traffic congestion alongUS 171 South BoundLane

Temporary Traffic

Signals


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Temporary Traffic Signals installed at

intersection of LA 8 and US 171


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Sequence of Construction - Phase II


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Sequence of Construction - Phase III


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Removed temporary traffic signals

Staged flagmen at each access point into the

roundabout

Utilized dynamic message signs cautioning

traveling public that roundabout is open and there

is a yield condition ahead

Installed do not enter signs on temporary stands at

each connection point to the roundabout


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General Public Comments andEnd Results

All of the Politicians and most of the general public

have very favorable comments in regards to the

functionality of the Roundabout

From 2007 to 2010 there was an average of 10

injuries per year with only 1 fatality during that time

period.

Since 2010 there has only been one injury, which

occurred in January 2013.


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End Results

Si C i b t th Al d i


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Size Comparison between the AlexandriaSouth Traffic Circle and the LeesvilleRoundabout

Photo of the intersection of LA 8 and


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Photo of the intersection of LA 8 andUS 171, prior to construction

Proposed

Market Basket

location


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Completed Roundabout Aerial Photo of theintersection of LA 8 and US 171

Photo taken by SURDEX Corporation


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Q ti ?


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Questions ?

S51_US 171 at LA 8 Roundabout - Before and After Safety and Operations_LTC2013

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Transcript of S51_US 171 at LA 8 Roundabout - Before and After Safety and Operations_LTC2013