Bituminous pavement

1. HIGHWAY ENGINEERING
AND TRAFFIC ENGINEERING
CENG 95

2. The bituminous pavement is a
combination of mineral aggregate
and bituminous binders. The
mixture of rock material particles
with asphalt has created so many
names such as:
BITUMINOUS
PAVEMENT

3. –Plant mix
–Asphalt sheet
–Road mix
– Armor coat
–Oil mat, etc.
–Asphalt macadam
–Asphaltic concrete
–Mastic
–National paving

5. Qualities of asphalt road
•The surface must free from cracks or
raveling due to shrinkage and fatigue
failure
•It must withstand weather condition,
including the effect of surface water, heat,
cold and oxidation

6. •It must be resistant to internal moisture
such as water vapor
•It must posses a tight or porous
impermeable surfaces the case may be
suitable to underlying base on sub-base
•It must be smooth riding and skid free
surface

7. •The success of an asphalt pavement lies
or depends of the construction quality of
the sub-grade, and the base course. On
the contrary, pavement failure would be
considered as a forgone conclusion.

8. A satisfactory asphalt pavement
could be attained under the
following construction
procedures:

9. •Viscous asphalt binder is heated to a fluid
condition and mixed with heated
aggregates. The mixture is then laid and
compacted while still hot.
•Mixing liquid or emulsion asphalt with
aggregates at normal temperature is either
by plant or road mixing. The mixture is laid
and compacted at the normal temperature
before the solvent evaporates or the
emulsion breaks.

10. •Spread and compact the clean crushed
stones, sprayed with heated or emulsified
asphalt binder over it. Cover the sprayed
pavement with fine aggregates. This
process is referred to as the penetration
method.

11. BITUMINOUS
CONCRETE PAVEMENT

12. •Term asphalt concrete refers to a dense
graded road surface made of hot mineral
aggregates, mixed with hot asphalt and
laid at high temperature with about 275
degree farenheight to 300 degree
farenheit.

13. •Highest type of dense bituminous
pavement concrete suitable for the most
heavily traveled roads. A prime coat is first
applied and treated base before asphalt
concrete is laid. The purpose is to bind
any loose particles of the base and
likewise act as bond between the base
and the pavement to deter rising moisture
from penetrating the pavement.

14. •The thickness of compacted asphalt
concrete pavement ranges from 2 inch for
lightly traveled road to 6inch or more for
roads where traffic is considerably heavy.

15. BITUMINOUS
CONCRETE
PAVEMENT
FAILURES

16. •Caused by excessive loads. Heavy loads
creates deflection on the road surface,
with insufficient underlying strength.
Repetitious underlying of the excessive
load with roughen and crack the road
pavement will ultimately result to complete
failure of the roadway

17. •. Deflection on the road surface may be
the effect of the elastic deformation from
the consolidation of the base or subsoil or
from the combination of elastic and plastic
deformation. Repeated heavy wheel load
on highly resilient soil causes deflection
leading to fatigue failureof the asphalt
surface.

18. •Alligator or the map cracking of the
surface will be substantially evident.
Elastic deformation in the sub-grade
penetrate to depth of 6meters although
mostly to a depth from the surface.

19. •Surface failure
•Base failure
•Basement failure

24. MACADAM

26. •John Loudon McAdam was born in
Ayr, Scotland in 1756. In 1787 he
became a trustee of the Ayrshire
Turnpike in the Scottish Lowlands
and during the next seven years this
hobby became an obsession. As
Surveyor-General of roads for the
Bristol Turnpike in 1816, McAdam
first put his ideas about road
construction into major practice.
MACADAM

27. •He also began to actively propagate
his ideas in two booklets called
Remarks (or Observations) on the
Present System of Roadmaking,
(which ran nine editions between
1816 and 1827) and A Practical
Essay on the Scientific Repair and
Preservation of Public Roads,
published in 1819.

28. MACADAM is a type of road
construction pioneered by the
Scotsman John Loudon McAdam in
around 1820. The method simplified
what had been considered state-of-the-
art at that point. Single sized aggregate
layers of stone with a coating of binder
as a cementing agent are mixed in an
open-structured macadam.

29. •McAdam's method was simpler, yet more
effective at protecting roadways: he
discovered that massive foundations of
rock upon rock were unnecessary, and
asserted that native soil alone would
support the road and traffic upon it, as
long as it was covered by a road crust that
would protect the soil underneath from
water and wear.
[9]

30. MC ADAM'S METHODS
•McAdam's method was more simple
and yet more effective at protecting
roadways: he discovered that
massive foundations of rock upon
rock were unnecessary, and asserted
that native soil alone would support
the road and traffic upon it, as long as
it was covered by a road crust that
would protect the soil underneath
from water and wear.

31. •Size of stones was central to the
McAdam’s road building theory. The
lower 200 mm road (7.8 inches)
thickness was restricted to stones no
larger than 75 mm. (2.9 in) The upper
50 mm (1.9 in) layer of stones was
limited to 20 mm size (.787 in ) and
stones were checked by supervisors
who carried scales.

32. •A workman could check the stone
size himself by seeing if the stone
would fit into his mouth. The
importance of the 20 mm stone size
was that the stones needed to be
much smaller than the 100 mm width
of the iron carriage tires which
traveled on the road.

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