1 / 46

Concrete (PCC) Mixture Designs for O’Hare Modernization Program

Concrete (PCC) Mixture Designs for O’Hare Modernization Program. Principal Investigators Prof. Jeff Roesler Prof. David Lange. PROJECT GOAL

felicia-clements
Télécharger la présentation

Concrete (PCC) Mixture Designs for O’Hare Modernization Program

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Concrete (PCC) Mixture Designs for O’Hare Modernization Program Principal Investigators Prof. Jeff Roesler Prof. David Lange PROJECT GOAL Investigate cost-effective concrete properties and pavement design features required to achieve long-term rigid pavement performance at Chicago O’Hare International.

  2. Acknowledgements Principal Investigators • Prof. Jeff Roesler • Prof. David Lange Research Students • Cristian Gaedicke • Victor Cervantes

  3. Former OMP Research Students • Sal Villalobos – CTL, Inc. (Chicago area) • Civil engineer • Robert Rodden – American Concrete Pavement Association (Chicago area) • Technical director • Zach Grasley – Texas A&M • Materials professor

  4. Project Objectives • Develop concrete material constituents and proportions for airfield concrete mixes • Strength • volume stability • fracture properties • Develop / improve models to predict concrete material behavior • Crack width and shrinkage • Evaluate material properties and structural design interactions • joint type & joint spacing (curling and load transfer) • Saw-cut timing

  5. FY2005-06 Accomplishments www.cee.uiuc.edu/research/ceat • Tech Notes (TN) - • TN2: PCC Mix Design • TN3: Fiber Reinforced Concrete for Airfield Rigid Pavements • TN4: Feasibility of Shrinkage Reducing Admixtures for Concrete Runway Pavements • TN11: Measurement of Water Content in Fresh Concrete Using the Microwave Method • TN12: Guiding Principles for the Optimization of the OMP PCC Mix Design • TN15: Evaluation, testing and comparison between crushed manufactured sand and natural sand • TN16: Concrete Mix Design Specification Evaluation • TN17: PCC Mix Design Phase 1

  6. FY2006 Accomplishments www.cee.uiuc.edu/research/ceat • Tech Notes (TN) - • TN21: An Overview of Ultra-Thin Whitetopping Technology • TN23: Effect of Large Maximum Size Coarse Aggregate on Strength, Fracture and Shrinkage Properties of Concrete • TN24: Concrete Saw-Cut Timing Model • TNXX: Recycled Concrete Aggregate Concrete (80%) • TNYY: Functionally Layered Concrete Pavements (70%) • TNZZ: Properties of concrete containing GGBFS • TNAA: Effects of Concrete Materials and Geometry on Slab Curling (40%)

  7. Presentation Overview • 2006 Topics – TN & Brown Bag • Large-sized coarse aggregate mixtures • Slab Curling –theoretical analysis • Saw-cut timing model • Recycled Concrete Aggregate • P-501 Accomplishments • P-501 Remaining Items • Field Demo Project • Future Work

  8. Phase II Mix Summary Effect of larger-size coarse aggregate on strength Larger-size coarse aggregate

  9. Drying Shrinkage – Phase II Effect of larger-size coarse aggregate on shrinkage

  10. Fracture Energy Results-Phase II Effect of larger-size coarse aggregate on fracture properties • Age = 28-days

  11. P-501 Accomplishments • No fly ash replacement ratio • ASTM C157 <0.045% at 28-days* • MSA 1.5 inch* • Design strength 650 psi and specified strength =620 psi • Min. cement content =535 lb/yd3 • Min. w/cm 0.4 & max 0.45

  12. P-501 Remaining Issues • Nominal vs. Maximum Size Aggregate • Combined Gradation • ASTM C1157 – blended cements • Performance spec • Air content • 5.5% for 1.5inch MSA • Slag

  13. ASTM C 1157

  14. Combined Gradation

  15. Saw-Cut Timing and Depth • Process • Concrete Mix • Aggregate size • Cementitious content Crack Propagates FRACTURE PROPERTIES Wedge Split Test FEM Model Saw Cut Depth Model

  16. Summary of Notch Depth Requirements

  17. Recycled Concrete Aggregate (RCA) Objectives Determine the fracture properties of concrete • virgin and recycled coarse aggregate • w/ and w/o structural fibers • Effects of concrete drying shrinkage with recycled coarse aggregate

  18. Results – Virgin vs RCA • Similar peak loads • Virgin GF is 1.6 times larger than RCA GF

  19. Results – Virgin FRC vs RCA FRC • Similar peak loads • Similar softening curves • Similar GF

  20. RCA Shrinkage

  21. Concrete Slab Behavior • Curling stresses • temperature • moisture • Joint Opening • Load transfer • Dowel vs. no dowel

  22. Hygro-thermal Strain (1) • Quantify the drying shrinkage due to RH change • Micro-mechanical model: modified Mackenzie’s formula

  23. Hygro-thermal Strain (2) • Kelvin-Laplace equation

  24. Slab-base friction L: joint spacing Expansion caused by friction (after K.P. George)

  25. Joint opening ()

  26. Field Validation • Field data: three concrete slabs were cast on 06/22/06 at ATREL • Slab size: 15’x12’x10’’, BAM • Temp., RH measured @ surface, 1’’,3’’,5’’,7’’ and 9’’ at 15-min. interval • Two LVDTs installed in each joint to measure joint opening

  27. Joint Opening Measurement

  28. Two week joint opening

  29. Two month joint opening

  30. Concrete Free Shrinkage

  31. Material inputs • Setting temp. T= 50°C (122°F) • =5.75 x 10-6/°F (10.35 x 10-6/°C) • K=2.12 x 106 psi • Ks=3.77 x 106 psi • E=4.03 x 106 psi • Unit weight =149 pcf • Friction coeff. = 2.5 • Data set: 0:08a.m. on 07/01/06 –12:38p.m. on 07/13/06 at 15-min. interval

  32. Predicted joint opening(1)

  33. Predicted joint opening(2)

  34. Future Work

  35. Concrete Pavement / Material Interaction • Hygro-thermal effects on slab behavior • Curling & joint opening (slab sizes) • Dowel • Construction practices (curing, temp, mix components) • Early & long age • Material effects (e.g.) • Combined gradation* • Slag • High early strength/stiffness • FRC

  36. Surface Energy Balance Solar radiation Reflected radiation Convection Wind Conduction PCC slab BAM ASB Subgrade Conduction

  37. N-layer Heat Transfer Model Layer 1 Layer 2 Layer n B.C.s • Governing PDE

  38. QUESTIONS • www.cee.uiuc.edu\research\ceat • Thanks!

  39. Curling Questions • How does shrinkage effect slab size? • What are the combined effect of moisture/temperature profile? • What is the role concrete creep? • How do other concrete materials behave – FRC & SRA?

  40. Slab Curling  Stress  s s s s Time • Effects of materials and slab geometry on moisture and temperature curling after Grasley (2006) & Rodden (2006)

  41. Field vs Lab Lab Field

  42. Ground Granulated Blast Furnace SlagGGBFS

  43. Introduction • By product of the steel industry • Produced in blast furnaces • Highly cementitious • Hydrates similarly to Portland cement

  44. Production Iron blast furnace slag is quenched… it is then ground to a fine power

  45. Pros and Cons Improves workability Lower water demand Higher paste volume Higher strength potential Using 120 grade Longer setting time Decreased permeability Performs well in freeze thaw tests Reduces the effects of ASR Reduced heat of hydration* More susceptible to drying shrinkage Slower strength gain* Cons Pros

  46. Slag Activity Index ASTM C989 • Higher grade GGBFS can be used in larger percentages • Improves early and ultimate performance

More Related