6648193.ppt
- 1. SESSION 2 Concrete Pavement Type Selection and Design Features
- 2. Objectives Identify concrete pavement types Recognize considerations in type selection List concrete pavement design features and recognize their beneficial effects
- 3. Concrete Pavement Types Jointed plain concrete pavements (JPCP) Jointed reinforced concrete pavements (JRCP) Continuously reinforced concrete pavements (CRCP)
- 4. JPCP 3.7 to 6.1 m (typ.) (12 to 20 ft) Transverse Joints (with or without dowels) Longitudinal Joint (with tiebars) PLAN VIEW 3.7 to 6.1 m (typ.) (12 to 20 ft)
- 5. JPCP
- 6. JRCP PLAN VIEW 7.6 to 18.3 m (typ) (25 to 60 ft) Transverse Joints (with dowels) Welded Wire Fabric Reinforcing Longitudinal Joint (with tiebars)
- 7. JRCP
- 8. CRCP Longitudinal Joint (with tiebars) PLAN VIEW Typical Crack Spacing (0.9 to 2.4 m) (3 to 8 ft) Continuous Longitudinal Reinforcement (Deformed Bars)
- 9. CRCP
- 10. Pavement Type Factoids JPCP is the most common concrete pavement constructed today JRCP was widely constructed in 1960s and 1970s CRCP is constructed by a few agencies, often on high-volume, urban roadways
- 11. Considerations in Selection Traffic levels Subgrade Climate Initial construction and life-cycle costs Service life Future maintenance/rehabilitation Reliability Contractor experience Local experience/past performance
- 12. Pavement Characteristics JPCP Pavement Type Disadvantages Advantages CRCP JRCP Reliable design Applicable in all locations Fewer joints Less concern about random cracking No transverse joints Smooth riding Long service life Low maintenance Increased joint cost Increased joint maintenance Joint deterioration Crack deterioration High initial cost Rehab is difficult
- 13. NCHRP 1-32 Pavement Type Selection Guidelines 0 5 10 15 20 ESALs, millions Undoweled or Doweled JPCP Doweled JRCP CRCP 1.5 1.5- 3.0 3.0-6.0 Doweled JPCP Doweled JRCP CRCP Undoweled JPCP Undoweled or Doweled JPCP Doweled JRCP >6.0
- 14. Design Features Design elements contributing to performance Key design features (European researchers) – Nonerodible base course – Positive drainage – Strengthened structure (thick slab, doweled joints, or CRCP) – Slab stress relieving features (widened slabs, trapezoidal cross section)
- 15. Relative Effect of Design Features on JPCP Performance Initial smoothness Load transfer Subdrainage Base type Slab widening Joint spacing Slab thickness Slab modulus/strength Increasing Effect on Performance
- 16. Summary Concrete pavement types Considerations and selection Design features