Asphalt IssuesAsphalt IssuesAASHTO SCOCAASHTO SCOC

Virginia Beach, Va. Virginia Beach, Va.

By

Victor (Lee) Gallivan

FHWAAugust 2, 2011

HMA Topics for the Day

• Reclaimed Asphalt Pavement (RAP)

• Updated Thin 4.75 mm surface mixture

• Construction Specifications for IC

Recycled Materials SurveyRecycled Materials Survey

• Conducted through AASHTO SOM List Serve.• Sent end of December 2010.• Various questions related to RAP, RAS, RCA.• 45 state responses plus West Federal Lands and

Ontario.• Some data used is from 2007/2008 survey due

to lack of responses.

Survey Survey (cont)

• Main Survey Questions• Allowance of recycled materials (RAP, RAS,

RCA) per specifications?• Contractors actual usage of recycled materials?• Special testing/handling procedures?• Research needs, major concerns/obstacles for

increased usage of recycled materials?

RAP SurveyRAP Survey• Items of note from survey…

• RAP Availability – contractor/DOT ownership?

• WMA - Increased usage during DOT implementation?

• Stockpiles - Fractionation, captive stockpiles becoming more prevalent?

RAP Survey RAP Survey (cont)

• Research Needs:• Needed dwell time for mixing?• Mix performance tests (long-term durability,

thermal cracking, f/t resistance).• Binders - bumping, blending,

stiffness/cracking, interaction with polymers.• Determining RAP binder properties.• Skid resistance.

Since 2007/2008 Survey…Since 2007/2008 Survey…• RAP % allowed by percentage has stayed

pretty consistent for DOT’s.

• For RAP utilization by contractors, it appears the 20-30% usage has increased the most with all other percentages staying pretty much the same.

RAS SurveyRAS Survey• Items of note from survey…

• Sources – pre/post consumer supply (about 50/50).

• Special Requirements – gradations, asbestos testing.

RAS SurveyRAS Survey (cont)

• Research Needs• % binder contribution• Mix performance testing• Binder bumping, blending• Fatigue and low temperature cracking• Use in WMA?• Use of rejuvenators• Binder impacts

HMA Topics for the Day

• Reclaimed Asphalt Pavement (RAP)

• Updated Thin 4.75 mm surface mixture

• Construction Specifications for IC

Thin Lift 4.75 mm HMA Mix

• AASHTO M 323 Revisions• Gradation• Lay thickness• Acceptance (no cores)

Intelligent Compaction

Optimal pass

Target ICMV

DICMV<5%

FHWA Generic IC Spec

SubbaseSoils

HMA

Soils IC vs. HMA IC

• Soils IC• Moistures• Acceptance

• HMA IC• Temperatures• Acceptance

Components of Standards

1. Approval of IC Equipment

2. IC Data Requirements

3. Quality Control Plan

4. GPS/Datum Requirements

5. Test Sections and Target Values

6. QC/QA for Production Areas

7. IC Data Submittal

8. Payment and Measurements

1. Approval of IC Equipments

• Continuous Measurement System

• RTK GPS

• Onboard Reporting System

2. IC Data Requirements

• Compatible with Standardized IC Software (Veda)

• Headers• Manufacturer• Machine Type• Machine Model• Drum Width• Drum Diameter• UTM Zone…..

• Data Blocks• Date/time stamp• Long/Lat• Easting/Northing• Pass Counts• Speed• Frequency• Amplitude• Temperatures• IC Measurement Values

IC Analysis with Veda

3. Quality Control Plan

• Contract-Specific Quality Control Plan (QCP)

• Signed by Contractors

• Accepted by DOTs

• Implementation of QCP• QCP Field Manager• Quality Control Technician

4. GPS/Datum Requirements

• Datum Designation/Conversion

• GPS Checks

GPS Checks

5. Test Sections/Target Values

• Dimension of Test Sections• E.g., 75 m X 6 m for soils

• Evaluation for Each Lift Materials

• Fixed Settings of IC Compaction

• Determination of Target Roller Passes and IC-MV

QC Target Values

Optimal pass

Target ICMV

DICMV<5%

QA Target ValuesIC

MV

Target ICMV

Target % Gmm

% Gmm

6. QC/QA for Production Areas

• Mapping of Existing Support

• QC for Production Compaction• Coverage• Percent Requirements Meeting Target

Values

• Acceptance for Production Compaction• Based on Agency’s Current Requirements

Statistics of IC-MV

7. IC Data Submittal

• Daily Data Submittal

• Native IC Data

• Exported IC Data• All Passes Data• Proof Data

Courtesy of Bomag

All Passes and Proof IC Data

Courtesy of Sakai

…………..

…………..

N

E

Pass No. =1

Pass No.=2

Pass No.=3321

Legend of Pass No.

IX X

VII VIII

V VI

III IV

I II

•I, V and IX are same coordinate.•I I , VI and X are same coordinate.•I I I and VI I are same coordinate.•IV and VI I I are same coordinate.

All passes data Proofing data only

8. Payment and Measurements

• Lump Sum Payment• Itemized Payment

• Weekly IC Equipment Rental• Hourly Rate for Roller Operator

• Measurement• No. of calendar weeks roller furnished

• Unauthorized Work• Compacted materials are unauthorized without QC

data

Keys to Success

• Passion • IC Champions within Agencies

• Patience• It Takes Time!

• Communications• Among Agency, Suppliers, Contractors, and

Consultants

• Strategies• Start with Low-Hanging Fruits

Thank You !

Lee Gallivan, P.E.HQ-Office of Pavement TechnologyAsphalt Pavement EngineerVictor.gallivan@dot.gov