HIPERPAV Background and New Developments

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HIPERPAV Background and New Developments
15 November 2005 Madison, Wisconsin
presented by J. Mauricio Ruiz, P.E. Yadhira A.
Resendez
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(No Transcript)
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How did it start?

• Mid-80s
• 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

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How did it start?
Fast-track Findings

• Hot mixes on cold days?
• Blankets? Yes? No?
• Thermal shock? Curling/warping, cracking?
• Strength gain and opening time?
• Saw cutting and cracking?
• Internal stresses?

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How did it start?

• SP 201 (Fast-track) Findings
• Very positive results, but
• with two concerns
• What value to open to traffic?
• What about the influence of temperature
  on performance?

FHWA-SA-94-080
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Effects of Temperature Moisture
Time Period
First 72 hours
Service Life
Wearout
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JCP Distress Modes
Distress Type
Critical Stress Locations
Critical Period
Critical Stress Locations
Plastic Shrinkage Cracking
First 3-12 Hours or until Curing
Method Application
Thermal Shock Cracking
First 72 Hours
Plan Views
Edge Views
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Background

• HIPERPAV helps engineers and contractors

Understand 72-hour behavior
Predict 72-hour behavior of concrete pavements
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Paving Operations
800 AM
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Paving Operations
810 AM
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Curing
PCC Temp
Time
830 AM
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Environmental Influences
PCC Temp
Time
Overcast Conditions
Solar Radiation
Convection
Irradiation
Heat Conduction to/from the subbase
900 AM
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Heat of Hydration
PCC Temp
Time
Generated Heat from Hydration
1100 AM
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Set Time
PCC Temp
Transition from Plastic To Hardened State
Time
1200 PM
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Peak Concrete Temperature
PCC Temp
Slab Tends to Expand from Set Time up to the
Maximum PCC Temperature
Time
400 PM
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Cooling Begins
PCC Temp
PCC Slab Tries to Contract
Time
600 PM
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Joint Sawing
PCC Temp
Time
700 PM
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Curling
PCC Temp
Thermal Difference Through the Slab
Time
Cold
Warm
1100 AM
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Curling
PCC Temp
Bottom Expands Top Contracts Slab Tends to
Curl
Time
Cold
Warm
900 PM
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Curling
PCC Temp
Slab Weight Restrains Vertical Movement
DT
Time
900 PM
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Subbase Restraint
PCC Temp
Axial and Curling Restraint Lead to Crack
Formation at Joints
DT
Time
1200 AM
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Excessive Restraint
PCC Temp
As Temperature Decreases, PCC Contraction
Continues
DT
Time
200 AM
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Early-Age Failure
PCC Temp
DT
Time
Mid Panel Thermal Crack Occurs
500 AM
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Guidelines

• Complexity Galore
• Paper guidelines very limited use
• What about computerized modeling?
• Thus, was born

HIPERPAV
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Systems Approach

• In the past, many individual models have been
  developed to address pavement behavior
• HIPERPAV uses the Systems approach to unify all
  the models into one useful tool
• The Systems approach integrates
• Design parameters
• Material properties
• Environmental conditions
• Construction activities

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Superposition of Stresses
Top
Bottom
Axial
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Critical Stress
Top Bottom
Stress
Tension
Compression
Time
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JCP Stress and Strength Development
Magnitude of Stress or Strength
Magnitude of Stress or Strength
Time since Construction
Time since Construction
Scenario 1 Cracking should not occur
Scenario 2 Cracking may occur
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Baseline Case
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Baseline Case
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Question
Well, thats nice But, what if the weather is
not ideal?
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Cold Front
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Baseline Case
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Cold Front
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Question
What Now? Maybe some Blankets?
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Cold Front
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Cold Front Blankets
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Question
What happens if I have to open to traffic in 36
Hours?
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Cold Front Blankets
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Cold Front 36 Hours of Blankets
(Blankets removed at 36 hours)
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Question
Is there another way? What about a Fast-Track
Mix?
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Cold Front
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Cold Front Fast Track Mix
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What are typical uses?

• Predict responses in cold and hot weather paving
• Predict potential strength gain for tight
  closures and opening to traffic
• Determine effects of design parameters on stress
  development
• Joint spacing, thickness, base type
• Determine optimal mix characteristics
• Forensic studies crack development

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Recent HIPERPAV Validation
HIPERPAV was validated in ?Minnesota ?
Nebraska ? Arizona ? Texas ? N. Carolina
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HIPERPAV Versions
HIPERPAV 3.0
HIPERPAV 2.5
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Software Features

• New Graphical Interface ?
• Geographical Weather Database ?
• Analysis of Multiple Strategies ?
• Strategy Comparison ?
• Input Range Validation ?
• Reference Database ?
• Software Tutorial ?

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Software Features

• Cement and Admixtures Characterization ?
• Strength Conversion Tool ?
• Estimate Weather from Database ?
• Equivalent Age Maturity Method ?
• Slab Support Characterization ?
• Sawcutting Options ?
• PCC CTE and Shrinkage Inputs ?
• Tabular and Graphic Inputs ?

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Thank you!Any Questions?