2. Traffic noise is a growing problem, especially for
urban areas. The common noise mitigation measures
include noise barriers or earthberms that obstruct
sound propagation from the roadway to the
neighbouring community. Such costly measures are
infeasible or ineffective in many urban areas because
no actual noise reduction at the source is achieved.
Study has found tire-pavement interaction as the
major noise contributor at vehicle speed of >50 km/h
and pavement surface characteristics play an
important role in noise generation and propagation.
Construction of quieter pavements is therefore
considered to be promising technique for
economical/sustainable and environmental friendly
highway.
3. Quieter pavement is the term generally prefer
for the pavement that produce less noise
when vehicle tires rolling over it
Quieter pavements are most effective at
highway speeds with free-flowing traffic
when tire-pavement noise is the primary
contributor to the total traffic noise.
4. Engine
Exhaust system
Aerodynamic noise
Tire noise
The main contributor to
the traffic noise is
Tire/pavement noise
5. When tyre interact with pavement due to
mechanism high frequency sound is produce
• Mechanical vibration
• Air vibration
• Stick – slip effect
• Stick –snap effect
6. Trends and issues in mitigating traffic noise
through quiet pavements
(Praticò, Filippo G., and Fabienne Anfosso-Lédée)
7. This paper concentrate on the analysis of
trends and issue in mitigation of traffic noise
through the use of quiet pavement
8. 1. POROUS ASPHALT :-
It is the most efficient road surface
technology in terms of noise
reduction
Porous pavements consists of open
graded or uniformly graded
aggregate that provides void
content more then 20%
Porous pavements are capable of
reducing traffic noise, by absorbing
sound and provide natural drainage
Thickness of Single layer porous
asphalt is 40-50mm and shows
noise reduction of 5db
Thickness of double layer porous
asphalt is 50-90mm and shows
noise reduction of 8-9db.
9. It is a gap-graded asphalt mixture
with intermediate size aggregate
missing i.e contain larger stones in
which voids filled with considerable
amount of asphalt binder , fine
aggregate
• The typical air void content of SMA
mixtures is between 1.5 and 3.0%,
and the layer thickness is between 2
and 3 cm.
• The mixtures have both good
mechanical performance and friction
properties, and are applicable for a
normal traffic load
10. It is defined as the mix
contain made up of 20% of
rubber (scrap tyres) and has
void content 20-40% air
voids.
Thickness of bitumin layer is
15-40mm.
Provides elastic surface
which is beneficial in
absorbing noise produce by
vehicle tyres
Provide tyre pavement noise
reduction of about 5-15db
11. There is a strong focus on source-related
mitigation measures and an increasing
emphasis on costeffectiveness. Low noise
road surfaces are one of these cost-effective
measures and authorities have been
supporting their development for many years.
12. Development of tyre / road noise assessment
methodology in India
(Boodihal, M. A., Chethan, A., Swamy, R., Sahu, R., & Biligiri,
K. P.)
13. The major objective of this research study
was to develop a methodology to evaluate
tyre /road noise of various road type and
section in bangalore.
14. A noise trailer assembly was designed and developed to measure
field pavement noise of different surface.
15. Mild steel casing: was built as an acoustic
chamber with trapezoidal geometry
PVC is used as cushion lining inside the acoustic
chamber
Shaft is use to connect noise trailer axle and
parent vehicle
Two angle were used to connect axle and shaft to
prevent side movement of trailer
Noise meter socket : rectangular pipe with rubber
buds at one end and has noise meter in It which
is connected to computer through cables .
Distance between microphone of noise meter and
road surface was 25mm
16. • Noise trailer assembly along
with parent car was run on 3
different roadway surface and
noise measurement were
recorded and analysis
1.Asphalt concrete (AC)
2.Portland cement
concrete(PCC)
3.Plastic modified asphalt
concrete (PMAC)
17. Based on field test result obtained in study
following are the major conclusion
1. Effect of speed on tyre /road noise
Research studies indicate decrease in traffic
speed there is decrease in measured tyre /road
noise level
When average reduction in speed is 5km/h
Reduction in pavement noise level of
AC section is 2-3db
PCC section is 3-4db
PMAC section is 2-4db
18. PMAC section is noisiest among three road
section and not provide noise absorbing effect
and shows noise level of 6-8db compare with
AC mix, 3-4db compare with PCC mix.
PCC mix type is noisier then AC mix avg
difference is 4-6db.
AC is used as noise reducing material due to
its high porosity 4-6% in comparison with
PCC.
