construction of flexible pavement

summer training project

1. Construction of flexible pavement
by Rafi Khan(LPU)
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2. content
Introduction
Types of pavement
Components of flexible pavement
Construction of layers of flexible
pavement
Comparison of flexible and rigid
pavement
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3. What is a Pavement? Pavement is load Pavement is load
bearing and load distributary component of a bearing and load distributary component of a
road.road.
Flexible pavement Rigid pavement Flexible pavement Rigid pavement
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4. PURPOSE OF PAVEMENTPURPOSE OF PAVEMENT
1.1.Load support.Load support.
2.2.Smoothness. Smoothness.
3.3.Drainage.Drainage.
4.4.All weather operation.All weather operation.
5.5.Direction and guidance.Direction and guidance.
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5. Types of pavement
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PAVEMENTS
Rigid PavementsFlexible Pavements

6. Flexible pavement:Flexible pavements are so
named because the total pavement structure deflects, or
flexes, under loading. A typically composed of several layers
of material.
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7. Structure of flexible pavement
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8. Load distribution in flexible pavement
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9. Structure of Rigid pavement
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10. Load distribution in Rigid pavement
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11. Components of flexible pavement
Seal Coat
Surface course
Tack coat
Binder course
Prime coat
Base course
Sub-Base course
Sub-grade
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12. Components of flexible pavement
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13. Components of flexible pavement
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14. Subgrade: The subgrade is the compacted soil layer that
forms the foundation of the pavement system. It is also known
as the "Formation Level“.
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15. Construction of subgrade:
(a) Removal of top soil (If not suitable for sub
grade or to match the level)
(b) Removal of vegetation and other harmful
material
(c) Lay down the Soil in layers of 266mm (max.)
(d) Compaction of Layer ( After Compaction Max.
depth should be 200mm)
(e) Further Layer of Soil
(f) Compaction of Layer
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16. Preparation of subgrade
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17. Sub-base course: It is layer of granular material
provided above subgrade generally natural gravel. It is usually
not provided on subgrade of good quality.
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18. Construction of sub-base course
1. Sub-base layer is constructed on the top of the prepared
subgrade.
2.The sub-base material is spread to uniform thickness and
specific cross slope.
3.the moisture content of the material is checked and
additional quantity of water required to bring up to the
optimum moisture content is sprinkled at a uniform rate.
4. The loose sub-base layer is compacted by roller.
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19. Preparation of sub-base course
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20. Base course: This is the layer directly below the
surface course and generally consists of aggregates.
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21. Preparation of base course
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22. Prime coat:it is a low viscous bitumen
emulsion(60% bitumen+40% kerosene).
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23. Binder course:This layer provides the bulk of the
asphalt structure.  It's main purpose is to distribute load.
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24. Preparation of binder course
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25. Tack coat:it is high viscous bituminous material(100%
bitumen)
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26. Surface course: The surface course is the layer in contact
with traffic loads and normally contains the highest quality
materials.
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27. seal coat:it is the asphalt-water mixture to seal cracks on
surface layer.
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28. Flexible vs Rigid pavement
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29. THANK
YOU
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