Details:

Creators:
Young, Logan Michael ; Durham, Stephan ; Liu, Rui
Young, Logan Michael ; Durham, Stephan ; Liu, Rui Less -
Corporate Creators:
University of Colorado at Denver
Corporate Contributors:
United States. Federal Highway Administration
Subject/TRT Terms:
[+]
Anti-icing Bond Strength (Materials) Bridge Decks Costs Deicing Chemicals Epoxides Overlays (Pavements) Permeability Skid Resistance Surface Texture Tests
Publication/ Report Number:
CDOT-2014-2
Resource Type:
Tech Report
Geographical Coverage:
Colorado
Corporate Publisher:
Colorado. Dept. of Transportation. Applied Research and Innovation Branch
Abstract:
This study is the evaluation of two thin bonded epoxy overlays: SafeLane (marketed by Cargill), and Flexogrid

(developed by PolyCarb). SafeLane is advertised as an anti-skid/anti-icing overlay that stores deicing chemicals for

release during winter events. Flexogrid is an anti-skid overlay. These two products were compared on the basis of

physical properties, including mean texture depth, surface friction, bond strength, ability to stop chloride intrusion,

and anti-icing properties, as well as traffic safety and cost. Both overlays worked as intended when they were initially

applied on the bridge decks. Mean texture depth and friction testing have shown that they both provide a durable

wearing surface with good traction. All the SafeLane bond tests exceeded 250 psi (1.72 MPa). Flexogrid had initial

high bond strengths, but had varied failure modes. However, the delamination of the Flexogrid overlay was identified

on the bridge deck even after this product was reapplied. Permeability and chloride testing of the underlying concrete

decks indicated that both overlays work well to protect bridge decks from chloride ingress. Permeability was high, but

the chloride counts did not increase with age. The anti-icing property of SafeLane is effective when pre-charged with

deicing chemicals. The three sites evaluated in this study indicate a reduction in crashes, but further study is needed to

monitor the long-term performance in crash reduction.

Implementation

CDOT should use the information contained within this report to develop construction specifications for thin bonded

overlays. SafeLane can be considered for use on high crash rate bridges, where its high cost can be offset by an

increase in traffic safety. If SafeLane is to be used as an anti-icing overlay, it should have deicing chemicals applied

more often, and in smaller amounts. Pre-charging should be used when possible. Installation of Flexogrid should not

be considered on bridges before the reasons causing the delamination are investigated. Studies of both overlays should

continue so their long-term impacts on traffic safety can be analyzed.


Format:
PDF
Funding:
84.14
Collection(s):
US Transportation Collection
Main Document Checksum:
[+]
urn:sha256:b4bb7dee6a76d413477ea755ae9bf5d21ccdf2bce55dd9fe4cf95c8c3631873a
Download URL:
https://rosap.ntl.bts.gov/view/dot/27472/dot_27472_DS1.pdf
File Type:

Supporting Files

• No Additional Files

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