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    Rigid Pavement Design - Spring 2024

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    Zeeshan Abro

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    © All Rights Reserved
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    Rigid Pavement Design - Spring 2024

    Uploaded by

    Zeeshan Abro
    2 views12 pages

    Original Title

    Rigid Pavement Design_Spring 2024

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    2 views12 pages

    Rigid Pavement Design - Spring 2024

    Uploaded by

    Zeeshan Abro

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    © All Rights Reserved
    Download as PDF, TXT or read online from Scribd
    Download as pdf or txt
    of 12

    5/13/2024

    CE-342: TRANSPORTATION ENGINEERING – II

    Design of Rigid Pavements

    Dr. Muhammad Asif Khan

    Contents

    ➢Rigid Pavement Introduction and Concept


    ➢Rigid Pavement Design Aspects
    ➢ AASHTO Design Procedure and Example

    1
    5/13/2024

    Structure of the Pavement


    Recall the typical layered structures of Flexible Pavement
    and relate it to the Rigid Pavements:

    Flexible Pavement Rigid Pavement

    Rigid Pavement
    ➢PCC Is Much Stiffer Than HMA and Distributes the Load over a Much Wider
    Area

    Flexible Pavement

    Contact Pressure Contact Pressure


    100 psi 100 psi

    2
    5/13/2024

    Rigid Pavement

    Surface smoothness Thickness Design


    or rideability
    Longitudinal joint
    Transverse joint

    Surface Texture

    Concrete materials

    Dowel bars
    Tiebars
    Subgrade
    Base

    Jointed Plain Concrete Pavement (JPCP)

    Joint Spacing 15 – 30 feet

    3
    5/13/2024

    Jointed Reinforced Concrete Pavement (JRCP)

    Continuously Reinforced Concrete Pavement (CRCP)

    4
    5/13/2024

    AASHTO Method For Rigid Pavements


    1. Performance Period
    2. Traffic
    3. Reliability (R, S0)
    4. Environmental Effects
    5. Serviceability
    6. Effective Modulus of Subgrade Reaction
    7. Material Characterization (Ec, Sc’)
    8. Load Transfer Coefficient, J
    9. Drainage Coefficient, Cd
    10. Slab Thickness (Round to 1/2”)

    Major Findings – Rigid Pavements (AASHO)

    ➢ Slab Thickness Is the most important design variable


    ➢ Cracks are associated with loads

    ➢ Pumping was the major factor causing failure of

    sections with subbase


    ➢ More Pumping along the Edge

    ➢ Corner Deflection Increases at PM

    ➢ Speed Reduces Strain and Deflection

    10

    10

    5
    5/13/2024

    Rigid Pavements
    Pumping
    ➢ Seeping or ejection of water from
    beneath the pavement through
    cracks.
    ➢ In some cases, detectable by deposits
    of fine material left on the pavement
    surface, which were eroded
    (pumped) from the support layers
    and have stained the surface
    ➢ Excess moisture in the pavement
    structure, erodible base or subgrade
    materials, and high volumes of high-
    speed, heavy wheel loads

    11

    11

    Effective Modulus of Subgrade Reaction (AASTHO)

    ➢ Modulus of subgrade reaction, k instead of MR


    𝑀𝑅
    ➢ Composite k-value for Each Period 𝑘 =
    19.4

    ➢Effective Modulus of Subgrade Reaction (𝑘)


    ➢

    12

    12

    6
    5/13/2024

    Composite Modulus of Subgrade Reaction (AASTHO)

    13

    13

    Other Design Variables (AASTHO)

    ➢ Elastic Modulus of Concrete: Ec = 57,000(fc’)0.5


    ➢ fc’ is the compressive strength of concrete.
    ➢Concrete Modulus of Rupture: Sc
    ➢ Drainage Coefficient (Cd) Table 2.5
    ➢ Load Transfer Coefficient (J) Table 2.6
    ➢ ΔPSI
    ➢ Reliability (R) and Overall Standard Deviation (S0)
    ➢ Traffic 14

    14

    7
    5/13/2024

    Other Design Variables (AASTHO)

    15

    15

    Design Example – Rigid Pavement


    Given k = 72 pci, Ec = 5 x 106 psi, Sc = 650 psi, J = 3.2, Cd = 1 .0,
    delta PSI = 4 .2 — 2.5 = 1 .7, R = 95%, So = 0.29, and Wt = 5.1 x
    106 ,
    1. Determine thickness of slab.

    16

    16

    8
    5/13/2024

    Design Example – Rigid Pavement


    Given k = 72 pci, Ec = 5 x 106 psi, Se = 650 psi, J = 3.2, Cd = 1 .0,
    delta PSI = 4 .2 — 2.5 = 1 .7, R = 95%, So = 0.29, and Wt = 5.1 x
    106 ,
    1. Determine thickness of slab.

    17

    17

    Design Example – Rigid Pavement

    18

    18

    9
    5/13/2024

    TN-II-Spring 2022 19

    19

    TN-II-Spring 2022 20

    20

    10
    5/13/2024

    Rigid Pavement Construction - Reconstruction

    21

    21

    Construction - Surface Texture – Tine

    22

    22

    11
    5/13/2024

    Construction - Surface Texture – Light Broom

    23

    23

    Surface Texture –Drag Finish

    24

    24

    12

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