byRichard E. Root, P.E.

Root Pavement Technology, Inc.

Task 1 Literature ReviewTask 2 Cost AnalysisTask 3 General Review of

Wisconsin Accident DataTask 4 Develop Recommended

Procedures for OGFC Construction

Task 5 Final Report

Develop Recommended Procedures for OGFC Construction

Mixture DesignConstruction PracticesAcceptanceDraft Specifications

Following the completion of Task 1, a preliminary report will be prepared on the possible use of OGFC mixtures in Wisconsin. Work on the project will be temporarily halted at this point. The preliminary report will be reviewed by the TOC and a decision will be made on the future direction of the WHRP project. The following three options will be considered:

1. If the literature review looks promising and the TOC supports that position, work will continue on the project according to this proposal.

2. If the literature review indicates that the use of OGFC in cold weather is not a good idea and the TOC concurs, the project will be halted.

3. If the literature review indicates that the use of OGFC in cold weather is not a good idea and the TOC concurs, consideration will be given to adjust the research proposal to look at the use of a modified SMA mixture to provide some of the benefits of OGFC with out the problems.

Freeze early and last to thaw Difficult to remove snow and ice Surface subject to snow plow damage May need special deicing chemicals Require more treatments Cold weather and plows may accelerate raveling

Possible issue on bridge decks Problems with transitions to normal surface

Country Life - years

Europe 10

Australia 8-10

England* 7-10

Denmark 7

France 8-12

Country Life

Denmark 5 years

England* 86 percent

Australia 38-60 percent

Europe 50-80 percent

May be extended by cleaning the pores.

Approximate 15 percent increase in yield

Most agencies give it no credit in the pavement structure

May require special pavement marking

Requires more marking material Limited construction season

Fine Graded HMA

Coarse Graded HMA

SMA

Safety and the Law?Requires best practices on all projects

Where to use?High traffic to aid in cleaning mixture and justify added cost

Areas with high frequency of wet weather accidents

Balance against possible increase winter accidents

Should not be used on short segments or bridge decks

Construction issues?Requires paving at higher ambient temperature

High traffic areas may require night work Service Life?

Expect a substantial reduction in life compared to standard mixtures and/or SMA

Functional life significantly less than service life

Requires more construction and could result in more construction related accidents

Failure can be quite rapid at end of service life (worst case weeks)

Costs?Mixture 50 to 80 percent more than standard mix

Functional life less than half standard mix

Higher construction costs – markingsHigher winter maintenance costs

Repairs?Not ease to repair damage section of mix without losing drainage capabilities

Part 1Draft report submitted to TOCWaiting for responses from three states on current usage of OGFC

Reviewing references for added information for report

TOC review Part 1 report and provide guidance on the need for Part 2

Information is already available The recommendations would be presented in a table format

Responses from three of four key sources along with recommendation

Example

Item NCAT NCHRP 9-41 TTI Study Recommend

Mixture Design

Compaction

Gyratory 50 25 35 35

Marshall 50 - - -

Construction

Min Temp 60 70 60 60

Rolling Design voids

3 passes 1 pass 3 passes

Acceptance

Binder % NCAT oven Nuclear NCAT oven Recordation