hiperpav - institute for transportation early-age concrete pavement behavior using fhwa hiperpav 2....

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presented to:Midwest Transportation Consortium – Transportation Seminar

11 April 2003 – Ames, IA

Advanced Pavement Materials, Analysis,and Design

presented by

Dr. Robert Otto Rasmussen, P.E.Vice President and Chief Engineer

The Transtec Group, Inc., Austin, Texas, USA

Concrete Pavement Technology

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Concrete Pavement Research in the United States is currently focused in several areas:

Expedited Construction Practices (Fast-Track)Smoothness and Safety ImprovementsLong-Life PavementsOptimization of Materials and Construction

The Federal Highway Administration (FHWA), Concrete Industry, and the State Departments of Transportation (through TRB) are working more closely.

Introduction

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Topics3 topics of recent research with the objective of meeting these goals:

1. Predicting Early-Age Concrete Pavement Behavior using FHWA HIPERPAV

2. Concrete Mix Optimization – The Road to a Performance-Based Mix Design System

3. Whitetopping – A Proven Overlay with a New Name

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HIPERPAVMix OptimizationWhitetopping

Outline

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Outline

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FHWA-sponsored Research Project

State and Industry Involvement

Guidelines for Fast-track Jointed Concrete Pavements

orHIgh PERformance Concrete PAVing:an integrated computer system that analyzes material, environmental, design, and construction variables that will ....

HIPERPAVWhat is it?

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to understand 72-hour behavior

and

to predict 72-hour behavior of concrete pavements.

HIPERPAVWhat is it?

Assist Engineers and Contractors

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Mid-80’s

Concrete Paving Industry• Pave it fast• Time counts

or• Be ready to lose significant rehabilitation opportunities

After that message, over 100 trial projects were completed in US under SP 201.

HIPERPAVHow did it start?

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SP 201 (Fast-track)Findings

Very positive results with two major concerns:

1. What value to open to traffic?

2. What about temperature management? FHWA-SA-94-080


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Hot mixes; cold days? Blankets? Yes? No? Thermal shock?Curling & warping? Strength gain and opening time? Saw cutting and cracking? Internal stresses?

Fast-track Findings


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65°F

58°F

8:00 AM

75°F

HIPERPAV Paving Operations

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Time

PCC Temp

HIPERPAV

8:10 AM

Paving Operations

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Time

PCC Temp

HIPERPAV

8:30 AM

Curing

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Time

PCC Temp

Heat Conductionto/from the subbase

Convection

Overcast ConditionsSolar Radiation

HIPERPAV

9:00 AM

Environmental Influences

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Time

PCC Temp

Generated Heat from Hydration

HIPERPAV

11:00 AM

Heat of Hydration

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Time

PCC TempPCC SetTime

Transition from Plastic To

Hardened State

HIPERPAV

12:00 PM

Set Time

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Time

PCC TempSlab Tends to Expand from Set

Time up to the Maximum PCC Temperature

HIPERPAV

4:00 PM

Peak Concrete Temperature

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Time

PCC TempPCC Slab Tries to Contract

HIPERPAV

6:00 PM

Cooling Begins

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Time

PCC Temp

Saw Cut Joints Saw Cut Joints

HIPERPAV

7:00 PM

Joint Sawing

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Time

PCC Temp

Warm

Cold

Thermal Difference Through the Slab

HIPERPAV

11:00 AM

Curling

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Time

PCC Temp

Warm

Cold

Bottom Expands Top Contracts: Slab

Tends to Curl

HIPERPAV

9:00 PM

Curling

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Time

PCC Temp

∆T

Slab Weight Restrains Vertical

Movement

Slab Weight

HIPERPAV

9:00 PM

Curling

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Time

PCC Temp

∆T

Axial and Curling Restraint Lead to Crack Formation

at Joints

Formation of Cracks at Joints

Formation of Cracks at Joints

HIPERPAV

12:00 AM

Subbase Restraint

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Time

PCC Temp

∆TAs Temperature

Decreases,

PCC Contraction Continues…

HIPERPAV

2:00 AM

Excessive Restraint

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Time

PCC Temp

∆T

Mid Panel Thermal

Crack Occurs

HIPERPAV

5:00 AM

Early-Age Failure

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HIPERPAVControl Panel

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HIPERPAVIdeal Case

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HIPERPAVIdeal Case

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Well, that’s nice…

But, what if the weather is not “ideal”?

HIPERPAV Question

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HIPERPAVCold Front

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HIPERPAVIdeal Case

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HIPERPAVCold Front

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What Now?

Maybe some Blankets?

HIPERPAVQuestion

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HIPERPAVCold Front

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HIPERPAVCold Front + Blankets

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What happens if I haveto open to traffic in

24 Hours?

HIPERPAVQuestion

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Cold Front + Blankets HIPERPAV

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HIPERPAVCold Front + Blankets (remove @ 24 hrs.)

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Is there another way?

What about aFast-Track Mix?

HIPERPAVQuestion

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HIPERPAVCold Front

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HIPERPAVCold Front + Fast-Track Mix

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HIPERPAVDesign Inputs

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HIPERPAVMix Design Inputs

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HIPERPAVEnvironmental Inputs

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HIPERPAVConstruction Inputs

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Outline

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Outline

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Mix Optimization

Cost

Permeability

Strength

Stiffness

Workability

Coarse Aggregate

Fine Aggregate

Cement

Water

Mineral Admixtures

Chemical Admixtures

Models

“Optimum” PCC Mix

Criteria Constituents

Fibers

Plastic Shrink.

Performance

What is Optimization?

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☺“Yesterday”28-DayStrength

SpecRock Sand Cement

“Today” Multiple Cements

Multiple Sands

Multiple RockSources

Fly-Ashes, GGBFS,S. Fume, Nat. Pozz. Chem. Admixtures

Early Traffic Opening

Time

Warranty

PRS

Competition

Mix OptimizationMixes – Yesterday and Today

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Multiple Cements

Multiple Sands

Multiple RockSources

Fly-Ashes, GGBFS,S. Fume, Nat. Pozz. Chem. Admixtures

All Available Materials

KnowledgeBase

ComputerizedGuidelines

2 Cements

1 Sand

2 Rock Sources

1 Class F Fly-Ash1 GGBFS 2 Chem. Admix.

Subset of Materials

CementSandRock Class FFly-Ash

Chem.Admix.

Optimum Materials

OptimumProportions

Mix OptimizationRefining our Choices

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VariabilityCompatibility

Strength• Early-Age (< 72 hour)• “Spec” 3 to 56 Days• Long-Term (> 1 year)

Cost• Material Cost• Placement Cost• Life-Cycle Cost

MixProperties

• Coef. of Thermal Expansion• Shrinkage Potential• Stiffness / Creep Relaxation• Heat of Hydration and

Activation Energy

• Slump• Workability• Viscosity/Cohesion

Workability

Durability

• Permeability• Air Void Structure • Freeze-Thaw Susceptibility• DEF Susceptibility• ASR Susceptibility• Chemical Attack

• Fatigue Cracking Susceptibility• Spalling Susceptibility• Faulting Susceptibility• Smoothness Deterioration Potential

• Thermal Shock Potential• Plastic Shrinkage Cracking Susceptibility• Construction Smoothness PotentialDistress

Potential

Early-Age

Long-Term

Mix OptimizationProperty / Performance Targets

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Water

Cement • Chemistry• Fineness• Blending

Unit Cost of All Constituents

Aggregates• Gradation• Chemistry and Mineralogy• Thermal Properties (CTE, Conductivity, etc.)• Hardness• Texture and Shape• Permeability, Porosity, and Density

MineralAdmixtures

• Type (Fly Ash, GGBFS, etc.)• Chemistry• Fineness

ChemicalAdmixtures

• Type (AEA, HRWR, etc.)• Chemistry• Impact on Set Time

• Crushed Concrete• Industrial Byproducts / Waste

• Type (Chemical and Physical)• Strength, Stiffness, and Bond• GeometryOther

Additives

Fibers

Recycled

Polymers

Mix OptimizationMaterials Properties and Cost

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Fiber Dosage (% or lb./cu.yd.)

Workability(from Inverted Slump)

Fiber Type A

Fiber Type B

Fiber Type C

Mix OptimizationMaterial-Target Functions

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Fiber Dosage(% or lb./cy)

Workability(from Inv. Slump)


Cost ($)


Long-Term Perf.(Fatigue Life)


Early-Age Beh.(Plastic Shrink.)

Mix OptimizationMaterial-Target Functions

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Workability

DesirabilityCo

ntrac

tor100%

0%

Owne

r

Mix OptimizationDesirability Functions

☺

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Mix OptimizationDesirability Functions

Workability(from Inv. Slump)

Desirability☺

Cost ($)

Desirability☺

Long-Term Perf.(Fatigue Life)

Desirability☺

Early-Age Beh.(Plastic Shrink.)

Desirability☺

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$

LTPerf.

Workability40%30%

10%

20%

PlasticShrinkage

Mix OptimizationWeighting Factors

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Fiber Dosage (% or lb./cu.yd.)

Desirability100%

0%

OptimumFiber

Dosage

Mix OptimizationOverall Desirability

☺

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Outline

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Outline

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What is it?

Why was research needed?

What does this research provide?

Whitetopping

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What is it?

A new concrete pavement surface atop an existing hot-mix asphalt (HMA) pavement.

Whitetopping

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What is it?

Asphalt and Concrete...Working Together!

Whitetopping

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Why was Research Needed?

We understand HMA pavements...

Whitetopping

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For example... we know they rut...

Whitetopping

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and rut...

Whitetopping

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and rut...

Whitetopping

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and rut...

Whitetopping

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and rut...

Whitetopping

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and rut...

Whitetopping

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We also know they crack...

Whitetopping

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and crack...

Whitetopping

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and crack...

Whitetopping

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We also understand PCC pavements

Whitetopping

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We know they fault...

Whitetopping

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We know they fault...

Whitetopping

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We also know they spall...

Whitetopping

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We also know they spall...

Whitetopping

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And finally... we know they crack...

Whitetopping

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And finally... we know they crack...

Whitetopping

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But do we understand Whitetopping pavements???

? ?Concreteand Asphalt

Working Together

Whitetopping

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Common Questions...

Whitetopping

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Thin 4 in. to 8 in.Ultra-thin (UTW) < 4 in.

How thick do I build it?

Conventional 8 in. +

Whitetopping

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How much do I saw?Whitetopping

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How much do I saw?Whitetopping

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How do I prepare the surface?

Do I mill the asphalt?

Do I use a level-up course?

If so, how much?

Whitetopping

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Do I need Dowels, Fibers, Tie Bars?Whitetopping

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Common Questions...

... requiring practical and reliableanswers.

Whitetopping

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Materials Characterization Models

Hot-Mix Asphalt (HMA)Dynamic Modulus

η)f(///

abeff

beffa

HMA

ep)(ppp

)V(VV

Vp

)(ppE

log0.393532log0.3133510.60331343

283834

4

2200200

10.005470.0000170.0039580.00213.871977

0.8022080.0580970.002841

0.0017670.0292321.249937log

−−−++−++

+

+−−−

−+−=

Whitetopping

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Whitetopping

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Whitetopping

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Whitetopping

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Lane 5 Lane 6 Lane 7 Lane 8 Lane 9 Lane 10 Lane 11 Lane 12

Whitetopping

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Whitetopping

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Lane 12Lane 11Lane 10Lane 9Lane 8Lane 7Lane 6Lane 5 Lane 5 Lane 6 Lane 7 Lane 8Lane 9 Lane 10 Lane 11 Lane 12

Whitetopping

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Lane 5 Lane 6 Lane 7 Lane 8Lane 9 Lane 10 Lane 11 Lane 12

Lane 9Lane 5Lane 6Lane 10Lane 11Lane 12Lane 7Lane 8

Whitetopping

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Whitetopping

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05101520253035

0 5000 10000 15000 20000ALF Wheel Passes

Rut D

epth

(mm) Lane 9 Lane 5 Lane 6

Lane 10Lane 11Lane 12Lane 7

Lane 8

Whitetopping

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Lane 9 Lane 5 Lane 6Lane 10

Lane 11Lane 12Lane 7

Lane 8

Whitetopping

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Lane 9 Lane 5 Lane 6Lane 10


Lane 8

Lane 9Lane 5Lane 6


Lane 7Lane 8

Whitetopping

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Lane 9Lane 5Lane 6


Lane 7Lane 8

Whitetopping

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Lane 9Lane 5Lane 6


Lane 7Lane 8=

=======

Most-to-LeastSlab Cracking

Most-to-LeastHMA Rutting

¡ Holy Frijoles!

Whitetopping

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www.transtec.us

Thank You!!!

hiperpav - institute for transportation early-age concrete pavement behavior using fhwa hiperpav 2....

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