*Problems Associated with Bituminous Binders *BITUMINOUS PAVEMENT *Qualities of Asphalt Road *Bituminous Pavement Failure *Macadam Asphalt Mat

3. “PROBLEMS ASSOCIATED
WITH BITUMINOUS
BINDERS”

5. 1.) The thickness of asphalt film in the pavement, ranges from
.005 to .010mm. Test results showed that the thicker the
asphalt film, the lesser is the process of aging. Where
pavement has lower percentage of voids, aging is also
relatively low.

6. 2.)Mixtures are too dry, cracks and breaks easily.

7. 4.) Improper construction procedures can age prematurely. One
example is mixing asphalt with an overheated aggregate.

8. 6.) Climatic conditions can seriously affect the behavior
of asphalt penetration.

9. 7.) Different brand or source has variability in behavior.
The viscosity of some asphalt varies with
temperature from that of the others.
8.) An asphalt meeting a specified penetration
requirement at 77°F but with high viscosity
temperature ratio will become hard and brittle at
lower temperature.

10. BITUMINOUS PAVEMENT
Asphalt Macadam
Mastic
Asphalt Sheet
Road Mix
Oil Mat
Asphalt Concrete
National Paving
Plant Mix
Armor coat
“ASPHALT ROAD is virtually a
BITUMINOUS ROAD”

11. “Qualities of Asphalt
Road”

12. VISCOUS ASPHALT BINDER IS HEATED TO A FLUID CONDITION AND
MIXED WITH HEATED AGGREGATES. THE MIXTURE IS THEN LAID
AND COMPACTED WHILE STILL HOT.

13. 1.) The surface must be free from cracks or traveling due to shrinkage
and fatigue failure.
2.) It must withstand weather condition including the effect of surface
water, heat, cold and oxidation.
3.) It must be resistant to internal moisture such as water vapor.
4.) It must posses a tight or porous impermeable surface as the case
may be suited to underlying base on sub-base.
5.) It must be smooth riding and skid free surface.

14. Bituminous Pavement
Failure

15. Bituminous pavement failures are caused by excessive load.
 Repetitious application of excessive load will roughen and crack
the road pavement that ultimately result to complete failure of the
road way.
Repeated heavy wheel load on highly resilient soil causes deflection
leading to fatigue failure of the asphalt surface.

16. Macadam Asphalt Mat

17. Macadam is a type of road construction pioneered by Scottish engineer John
Loudon McAdam around 1820. The method simplified what had been
considered state of the art at that point. Single-sized aggregate layers of small
stones, with a coating of binder as a cementing agent, are mixed in an open-structured
roadway.

18. MACADAM ASPHALT MAT

19. Constructing the Macadam Asphalt Road

20. 1.) Spread the coarsest aggregate to the roadway. Compact with either smooth
wheeled roller or vibratory devices.
2.) Smoothness of the surface is checked after compaction. Low spots are
corrected by removing, replacing and recompacting the stones until smooth
surface is attained.

21. 3.) Apply asphalt by spreading the right amount of bitumen at specified
temperature. The lower the stone layer will not be coated if the
asphalt binder is too thick On the other hand, too fluid mixture will
cause running the binder down underlying layers

22. 4.) In placing the keystone base course, sufficient amount of smaller
stone is mixed and spread on top to fill the interlocking voids,
followed by compaction the spraying with asphalt binder.

23. 5.) Sealing of the surface is applied to seal the pavement against
moisture. These involve spreading of selected binder, spraying
and rolling of the cover aggregates.

24. 6.) During construction , the weather must be dry and warm. If not, it is better to used
emulsified asphalt as binder.
7.) Before the application of asphalt binder, coarse aggregate is first chocked with
smaller stone to seal the remaining top voids, followed by spraying emulsified asphalt
binder

25. Any Questions?

26. Please Say None..