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Question
State	IA
Description Text	We have a situation due to the recent cold weather that the epoxy holding the pins in the pavement froze, well below 20 deg. It is unclear what pullout strength these pins will provide. Do you know what pullout strength would be required by the design? My assumption was that the pin mainly functions as a sheer device but Chris Poole told me it does serve a pullout propose too. We are trying to decide what length we need to go to correct the situation. The RCE is going to talk to the manufacture to see if the epoxy will develop sufficient strength once it is warmed up. If that does not turn out favorably and the pullout strength is important to the design, what would recommend to for correcting the problem with the barrier in place? Thank you in advance. http://www.iowadot.gov/design/SRP/IndividualStandards/eba100.pdf

Question

State

IA

Description Text

We have a situation due to the recent cold weather that the epoxy holding the pins in the pavement froze, well below 20 deg. It is unclear what pullout strength these pins will provide. Do you know what pullout strength would be required by the design? My assumption was that the pin mainly functions as a sheer device but Chris Poole told me it does serve a pullout propose too. We are trying to decide what length we need to go to correct the situation. The RCE is going to talk to the manufacture to see if the epoxy will develop sufficient strength once it is warmed up. If that does not turn out favorably and the pullout strength is important to the design, what would recommend to for correcting the problem with the barrier in place? Thank you in advance.

http://www.iowadot.gov/design/SRP/IndividualStandards/eba100.pdf

System Performance Evaluation

System Types
Permanent Concrete Barriers

Applications

System Features

Date November 19, 2014
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Attachment BA-100.png

Response
Response (active)	We have looked briefly at the attached detail and have some thoughts. 1. What test level is this barrier designed for? 2. In looking at the design, the height, width, and reinforcement of the barrier suggest that the barrier would likely be sufficient to withstand TL-3 and TL-4 level impacts without counting on contributions from the epoxy adhesive anchors. If TL-5 is the target, we would need to perform additional calculations regarding the capacity. 3. If it turns out that the epoxy will not set following a warm up and additional capacity is required, the simplest solution for providing additional capacity would be to provide a 2” deep asphalt keyway on each side of the barrier. We have done similar setups in the past and they have worked acceptably. Let me know if you need more information.

Response

Response
(active)

We have looked briefly at the attached detail and have some thoughts.
1. What test level is this barrier designed for?

2. In looking at the design, the height, width, and reinforcement of the barrier suggest that the barrier would likely be sufficient to withstand TL-3 and TL-4 level impacts without counting on contributions from the epoxy adhesive anchors. If TL-5 is the target, we would need to perform additional calculations regarding the capacity.

3. If it turns out that the epoxy will not set following a warm up and additional capacity is required, the simplest solution for providing additional capacity would be to provide a 2” deep asphalt keyway on each side of the barrier. We have done similar setups in the past and they have worked acceptably.

Let me know if you need more information.

Date November 19, 2014
Previous Views (130) Favorites (0)

Response
Response (active)	This is a TL-4 rail, so it sounds like we will be OK even if the epoxy does not make full strength. Thank you for getting back to me on this so quickly.

Date November 19, 2014
Previous Views (130) Favorites (0)

Question on our BA-100 Standard Road Plan