Performance of Exposed Aggregate Surface of Composite Pavements at MnROAD Bernard Izevbekhai Alexandra Akkari Minnesota Department of Transportation International.

Performance of Exposed Performance of Exposed AggregateAggregateSurface of Composite PavementsSurface of Composite Pavements at MnROAD at MnROAD

Bernard IzevbekhaiBernard IzevbekhaiAlexandra AkkariAlexandra AkkariMinnesota Department of TransportationMinnesota Department of Transportation

International Symposium on Pavement Performance Trends Advances and International Symposium on Pavement Performance Trends Advances and ChallengesChallenges

ASTM Committee E17 on Vehicle Pavement SystemsASTM Committee E17 on Vehicle Pavement SystemsTampa FloridaTampa Florida

December 5 2011December 5 2011

OUTLINE

Introduction Introduction LayoutLayoutMix DesignMix DesignPerformance EvaluationPerformance EvaluationResultsResultsConclusionConclusionPotentialsPotentials

MNROAD MAINLINE

• Interstate 94 Westbound Live Traffic• 28,000 AADT• Mainline • Passing Lane Vs. Driving Lane 50-50 Traffic; 80-20

ESALs• Total Truck Volume 15% approx.

Introduction• Targets of EA Surface• Quiet pavement surface• Increased durability• Increased friction

• Objective of Composite Pavement• Minimize cost with high

quality EA surface layer over low cost (relaxed gradation) layer

• Sustainability• Investigate Cost

effectiveness of 2-lift Concrete

Cell 70 Cell 71 Cell 72Innovative Diamond

Grind

Traditional Diamond

Grind

Exposed

Aggregate

3" HMA 3" EAC 3" EAC

6" RAC 6" RAC 6" CHP

8" Class 5 8" Class 6 8" Class 7

Clay Clay Clay

Composite CellsCompare EAC to cells 70 and 71 to evaluate performance

Mix DesignFly Ash 15%

Water (lbs/cy) 283

Cement (lbs/cy)(Type I/II) (SG=3.15) 616

Fly Ash (lbs/cy)(Class C/F) (SG = 2.5) 109

W/CM 0.39

C. Sand (OD lbs/cy)(SG = 2.63) (Abs= 0.90%) 843

CA1 (OD lbs/cy) (1/2” W. Chips, SG=2.72, Abs= 0.40%) 1133

CA2 (OD lbs/cy) (3/8” W. Chips, SG= 2.72, Abs= 0.40%) 843

Max Slump (in) 3% Air 7

Multi-Air 25 (oz/cy) 2 - 15

Adm 686 (oz/cwt) 1 - 5

Adm 3 (oz/cwt)(as needed for slump retentions) 0-5

98% Passing 3/8”

Performance Evaluation

On Board Sound Intensity AASHTP TP 76-09

Friction ASTM E-247

International Roughness IndexASTM E-950

Profile DepthASTM E-2157

Sound Absorption ASTM E-1050

Ride Quality

Anomalous laser-induced IRI was not observed in EAC.

Pavement Noise

Sound Absorption

Friction

Surface Profile

TextureOrientation

SPIKINESS CONCEPT & QUANTIFICATION

dx

SKU =

Conclusions• EAC does not provide significant noise reduction• higher OBSI than both the HMA and traditional diamond grind.

• Innovative diamond grinding of composite pavements may be beneficial for noise reduction• lower OBSI than the HMA, EAC, traditional DG surfaces, and higher sound absorption than EAC.

• EAC can provide more than adequate friction for driver safety, but does not show any improvement from typical HMA or DG.

• Anomalous laser-induced IRI was not observed in EAC.

Going Forward• Changing the quality and type of aggregate in EAC could lead to a

change in texture orientation / spikiness and improve surface performance.

• Need to examine Elongation, flatness etc in mix design to minimize spikiness.

QUESTIONS

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