Concrete and Concrete Pavements Research Group

1. Concrete and Concrete Pavements Research Group

2. Meet the research team… 3 PhD Students 4 MS Students 1 Undergrad

3. What do I do…… Material Characterization Instrumentation Modeling

4. Material Characterization Instrumentation Modeling

5. Components of concrete Coarse Aggregate Fine Aggregate Cement & SCM’s Water

6. Microstructure Mixture Constituents http://pittsburgh.about.com/library/pictures/bridges/uc_bridge-12.htm Material Properties Structures Materials: Multi-scale solutions

7. Development and evaluation of engineered pcc materials • Dimensional stability/compatibility (drying shrinkage, thermal coefficient, creep…) • Strength (split tensile, flexural, compressive) • Stiffness (dynamic & static) • Fracture toughness • Surface texture • Abrasion resistance • Durability (chemical and freeze-thaw)

8. Characterization of material properties through laboratory testing

9. Material Characterization Instrumentation & Modeling

10. Pavements 101

11. Stress: Uniform drops in temperature and moisture Restraint Conditions Friction Moisture andHeat Thermal & Moisture Conditions

12. + _ Negative gradient Stress: Nonuniform changes in temperature and moisture Temp. or Moist. + _ Positive gradient

13. + _ Negative gradient Stress: Combined load and Gradients Temp. or Moist. + _ Positive gradient

14. Moisture andHeat Construction Gradient

15. Construction Gradients Zero Stress Condition Stress as a Result of the Construction Gradient Moisture andHeat At set: Slab Temperature = 105 F Gradient = +0.5 F/in Gradient = 0 F/in

16. Measuring Slab Response to Environmental and Applied Loads Instrumentation- Useful in the calibration/validation of models.

17. Pavement Design Bridge Design • Define critical load and axle configuration • Accumulate damage of each vehicle load for each hour of the day of each mth of the year

18. n S N Pavement Design PROCESSED INPUTS FATIGUE DAMAGE MODEL STRUCTURAL MODEL s, e, d Traffic, moisture & temperature prediction models, material models • INPUTS • Layer thickness • Material properties • Environmental conditions • Axle loads and volumes CALIBRATION WITH FIELD DISTRESS • OUTPUTS • Cracking • Faulting • IRI

19. Time increment PCC Strength CTB Traffic Base Modulus No Units Subgrade Modulus 0 2 4 6 8 Time, years Models Consider Changing Conditions

20. Current Design Approach: • INPUTS • Slab thickness • k-value • ESAL • PCC Mr STATISTICAL REGRESSION MODEL • OUTPUTS • PSI • Concrete Mixture Properties: • Modulus of rupture (28 day) • Elastic Modulus (28 day)

21. New MEPDG Design Guide Inputs • Concrete Mixture Properties: • Modulus of rupture (7, 14, 28 & 90 day, 28 day to 20 yr ratio) • Elastic modulus (7, 14, 28 & 90 day, 28 day to 20 yr ratio) • Poisson’s ratio • Unit weight • Thermal coefficient of expansion • Drying Shrinkage • Thermal conductivity • Heat capacity • Mixture Design Information • Cement type • w/c ratio • Aggregate type • Set Temperature Information • Zero stress temperature • Zero stress temperature profile

22. Currently Funded Projects

23. n N S 1. Project Title:Evaluation of the R1-37A Rigid Pavement Design Procedure Sponsoring Agency:Federal Highway Administration Pitt Expenditures/Duration:$100,000/1 year Collaborators:ARA, AET PI: J. Vandenbossche PROCESSSED INPUTSTraffic, moisture & temperature prediction models, material models STRUCTURAL MODEL FATIGUE DAMAGE MODEL s, e, d • INPUTS • Layer thickness • Material properties • Environmental Conditions • Axle Loads and Volumes • OUTPUTS • Cracking • Faulting • IRI CALIBRATION WITH FIELD DISTRESS

24. 2. Project Title:Investigate the Design and Construction of Composite Pavement Systems Sponsoring Agency:SHRP 2/National Academy of Science Pitt Expenditures/Duration:$102,000/4 year Collaborators:ARA, U of Mn & UCDavis PI: M. Darter A PCC surface placed over a just placed PCC layer (“wet on wet”). (Bolander et. al. 2007) • Objective: Focus on debonding, built-in curl and joint (crack) formation • Pitt’s Role • Instrumentation of test sections • Use of instrumentation data for model calibration/validation

25. NDT Load NDT Sensors r D 3. Project Title:Using Falling Weight Deflectometer Data with Mechanistic-Empirical Design and Analysis Sponsoring Agency:Federal Highway Administration Pitt Expenditures/Duration:$51,000/1.5 year Collaborators:ApTech, MSU PI:K. Smith Rigid Pavements • Backcalculate layer properties • Detect voids • Characterize joint performance

26. 4. Project Title:The Development of a Design Procedure for Thin and Ultra-Thin Concrete Pavements Sponsoring Agency:Federal Highway Administration Pitt Expenditures/Duration:$330,000/3 year PI:J. Vandenbossche • Primary Concerns • Characterize effects of fibers • Bond strength/degradation Adapted from ACPA & Rosler

27. Moisture andHeat 5. Project Title:Establish Inputs for the New Rigid Component of the Mechanistic-Empirical Pavement Design Guide Sponsoring Agency:PennDOT Pitt Expenditures/Duration:$509,000/3 year PI:J. Vandenbossche • Primary Efforts • Material characterization • Pavement instrumentation

28. 6. Project Title:Premature Deterioration of Jointed Plain Concrete Pavements Structural Model Sponsoring Agency:PennDOT Pitt Expenditures/Duration:$257,000/1.5 year PI:J. Vandenbossche • Material Characterization • Strength development • Fracture toughness • Thermal coefficient • Drying shrinkage • Environmental loads • Axle loads and volumes