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Request to use IaDOT Concrete Barriers

Question
State NE
Description Text
 I am interested in your opinion regarding the following request.

The NDOT is reviewing a request from Hawkins Construction Company.
They desires to build concrete protection barriers for regional use in NE and IA and they have requested permission to use concrete barriers constructed per the IDOT design on NDOT construction projects.

The two designs are attached. Please note the differences shown in red and orange.

As part of the review of this request, Mr. Jim Knott suggested that I get your opinion of the reduced surface area on the bottom of the IDOT-designed barrier (having the chamfer) vs the NDOR design without a chamfer. More specifically, do you think, the reduced are would result in unacceptable deflection of the barriers when struck at a location where they cannot be pinned (such as on a bridge deck).       

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From: Neemann, Matt
Sent: Thursday, July 19, 2018 3:19 PM
To: Dearmont, Andy
Subject: RE: Temporary Barriers

The only difference that I see is the “marker inset” that we have in our barriers. If this was not in there though, it can be accomplished in another way.





From: Dearmont, Andy
Sent: Thursday, July 12, 2018 1:24 PM
To: Neemann, Matt
Subject: FW: Temporary Barriers

Matt,
Hawkins is planning to make concrete barriers and are asking, if they make them in accordance with the attached Iowa standard, would they be acceptable for use on NDOT projects?

Phil indicates that they would need to comply with the loop-steel certificate submittal requirement.

Any concerns from Traffic?

Andrew W. Dearmont
Nebraska Department of Transportation
OFFICE 402-479-4451
andy.dearmont@nebraska.gov
dot.nebraska.gov | Twitter

From: TenHulzen, Phil
Sent: Friday, June 29, 2018 7:15 AM
To: Dearmont, Andy
Cc: Sorben, Nathan
Subject: RE: Temporary Barriers

Traffic owned the concrete barriers do they allow/ disallow?

On our std plan M&R gets the Loop steel certificate showing they meet the correct steel – If they can produce this; allow them.

Phil
From: Dearmont, Andy
Sent: Thursday, June 28, 2018 4:57 PM
To: TenHulzen, Phil ; Sorben, Nathan
Subject: FW: Temporary Barriers

Are you the individuals that can review and accept/deny this request?

Andrew W. Dearmont
Nebraska Department of Transportation
OFFICE 402-479-4451
andy.dearmont@nebraska.gov
dot.nebraska.gov | Twitter

From: Mike Olson
Sent: Thursday, June 28, 2018 3:42 PM
To: Dearmont, Andy
Subject: Temporary Barriers

Andy,
As discussed on the phone, can you take a look at the Iowa temporary barrier design and determine if they would acceptable as Type C barriers in Nebraska?

Thanks for your help.

Mike Olson
Hawkins Construction Company


Portable Barriers


Date July 20, 2018
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Attachment Iowa-NDOT PCB.jpg Attachment BA-401.pdf
Response
Response
(active)

With respect to the differences in the designs, I have the following comments.

 

  1. The chamfers on the underside of the barrier in the Iowa design should not pose and issue for the barrier in terms of is performance in a free-standing configuration. We have tested this design of free-standing PCB in the past both with and without that base chamfer and did not observe as significant difference in barrier performance or dynamic deflection. Barrier mass and friction on the ground are not greatly affected by the small amount of area removed. As such, we have no concerns with this.
  2. Iowa does not have the additional two drainage/lifting slots slots that NDOT uses on their PCB. NDOT discussed those additional slots for drainage prior to including them in the design and we concurred with their addition. We have some tests on the PCB design with two and four drainage/lifting slots, and have not observed any difference in the barrier performance.
    1. Previous review of NDOT design ---  https://mwrsf-qa.unl.edu/view.php?id=278
  3. Details in the link above also discuss the loop steel comments we had with NDOT previously.

 

Please let me know if you have further questions.

 

Thanks

Date July 20, 2018
Previous Views (306) Favorites (0)