SESSION 2 Concrete Pavement Type Selection and Design Features.

SESSION 2SESSION 2

Concrete Pavement Type Selection and

Design Features

Concrete Pavement Type Selection and

Design Features

ObjectivesObjectives

Identify concrete pavement types

Recognize considerations in type selection

List concrete pavement design features and recognize their beneficial effects

Concrete Pavement TypesConcrete Pavement Types

Jointed plain concrete pavements (JPCP)

Jointed reinforced concrete pavements (JRCP)

Continuously reinforced concrete pavements (CRCP)

JPCPJPCP

3.7 to 6.1 m (typ.)

(12 to 20 ft)

Transverse Joints(with or without dowels)

Longitudinal Joint (with tiebars)

PLANVIEW

3.7 to 6.1 m (typ.)

(12 to 20 ft)

JPCPJPCP

JRCPJRCP

PLANVIEW

7.6 to 18.3 m (typ)

(25 to 60 ft)

Transverse Joints(with dowels)

Welded WireFabric Reinforcing

Longitudinal Joint (with tiebars)

JRCPJRCP

CRCPCRCP

Longitudinal Joint (with tiebars)

PLANVIEW

Typical Crack Spacing(0.9 to 2.4 m)

(3 to 8 ft)

Continuous Longitudinal Reinforcement

(Deformed Bars)

CRCPCRCP

Pavement Type FactoidsPavement 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

Considerations in SelectionConsiderations in Selection Traffic levels

Subgrade

Climate

Initial construction and life-cycle costs

Service life

Future maintenance/rehabilitation

Reliability

Contractor experience

Local experience/past performance

Pavement CharacteristicsPavement Characteristics

JPCP

Pavement Type DisadvantagesAdvantages

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

NCHRP 1-32 Pavement Type Selection Guidelines

NCHRP 1-32 Pavement Type Selection Guidelines

0 5 10 15 20 ESALs, millions

Undoweled or Doweled JPCPDoweled JRCPCRCP

1.5

1.5-3.0

3.0-6.0

Doweled JPCPDoweled JRCPCRCP

Undoweled JPCP

Undoweled or Doweled JPCPDoweled JRCP

>6.0

Design FeaturesDesign 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)

Relative Effect of Design Features on JPCP Performance

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

SummarySummary

Concrete pavement types

Considerations and selection

Design features