Download - Technical review of R51-03 phase3 in Japan
Ministry of Land, Infrastructure, Transport and Tourism
Technical review of R51-03 phase3 in Japan
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Road Traffic Noise Reduction Measures in Japan
✓ To achieve 100% in the EQSs(Environmental Quality
Standards)for Road Traffic Noise
✓ To reduce the number of complaints related to vehicle
noise
◆ Targets
EQS: An administrative goal set as a standard that should be maintained for the
protection of human health and the preservation of the living environment, and
the standard value is set for each area type and time category.
.
◆ Technical review of R51-03 phase3
✓ Before introducing phase3, the following studies are nowbeing conducted in Japan
To assess the effectiveness of phase3 introduction at the
points exceeding EQSs, by using JARI prediction model
To conduct a survey of automobile manufacturers
regarding the impact of phase3 introduction, etc1
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Time-line
✓To sort out what is important as noise
countermeasures beyond phase3, we would like to
continue to share our issues and initiatives
including the technical review of phase3 in Japan.
✓We are planning to report an result of the review
at TF-VS early next year.
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Road traffic noise prediction model
based on micro traffic flow model
Japan Automobile Research Institute (JARI)
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Overview of the road traffic noise
prediction model
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Overview of the model
Features
➢ Power unit noise and tyre/road noise are treated as individual sound
sources.
➢ Running conditions and generated noise of individual vehicles in the
traffic flow are considered.
➢ Fluctuation of road traffic noise at sound receiving point is calculated
by summin up the sound propagates from each vehicle.
➢ Since the effect of noise reduction for each sound source can be
calculated individually, this model is suitable for estimating the
effectiveness of vehicle noise measures.
◆ This road traffic noise prediction model is a combination of
"micro traffic flow model" and "sound estimation model".
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Calculation flow
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Traffic condition of target road
Driving condition of each vehicle
Road traffic noise LAeq
Power unit noise
Traffic flow estimation
Sound power level of each vehicle
Noise fluctuation at recieving point
- Traffic volume for each vehicle category
- Vehicle speed- Traffic light control- Road dimension
Tire/road noise
Sound propagation
Traffic flow estimation(micro traffic flow model)
Road traffic noise estimation(sound estimation model)
騒音レベル[dB]
時間 [s]Time [s]
A-w
eig
hte
dS
PL
[dB
]
power unit noise
tire/road noise
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Traffic flow estimation
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Input data to the traffic flow model
Inflow traffic volume for each vehicle category by lane
Driving lane: Maximum speed when cruising
Traffic light placement, light indication time, Phase between
lights
Number of lanes, road dimensions, pavement type, etc.
To simulate actual traffic
flow, these values are
set based on the traffic
flow survey results
受音点-1
(交差点近傍)受音点-2
(定常走行区間)Receiving point-2
Cruising section
Receiving point-1
Near intersection
with traffic light
Inflow traffic volume of each vehicle category by each route
Vehicle speed when cruising in each section
indication time of traffic lights and phase difference between
them
Number of lanes, road dimensions, etc.
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Micro traffic flow model (car following model)
The coefficients α and β were determined based on the actual driving survey.
𝑑2𝑥
𝑑𝑡2= 𝛼 𝑉𝑜𝑝𝑡𝑖𝑚𝑎𝑙 − 𝑉𝑓𝑜𝑙𝑙𝑜𝑤 + 𝛽 𝑉𝑙𝑒𝑎𝑑 − 𝑉𝑓𝑜𝑙𝑙𝑜𝑤
𝑉𝑙𝑒𝑎𝑑 𝑉𝑓𝑜𝑙𝑙𝑜𝑤
𝑉𝑜𝑝𝑡𝑖𝑚𝑎𝑙 𝑙
𝑙
➢ In the micro traffic flow model, car following model was adopted.
➢ Running condition of a following vehicle is estimated based on that of
a leading vehicle.
Running Condition: vehicle position, speed, acceleration, engine speed
and engine load
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0.0
1.0
2.0
3.0
4.0
0 25 50 75 100 125 150 175
Acce
lera
tio
n,
m/s
2
PMR
10 km/h
0.0
1.0
2.0
3.0
4.0
0 25 50 75 100 125 150 175
Acce
lera
tio
n,
m/s
2
PMR
40 km/h
0.0
1.0
2.0
3.0
4.0
0 25 50 75 100 125 150 175
Acce
lera
tio
n,
m/s
2
PMR
70 km/h
Micro traffic flow model (Leading vehicle)
The acceleration of the leading vehicle that accelerates from the
intersection is calculated by the following formula based on the results
of the driving mode survey in urban areas.
GRB-35-inf06 (2001.09,JPN)
Excerpt
𝑎 = 3.30 − 2.15 log10 𝑉 + 0.77 log10 𝑃𝑀𝑅
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Result of traffic flow estimation
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Road traffic noise estimation
-- Setting of sound souces and sound
propagation calculation
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Expression of sound power level for each sound source
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Sound source Experimental equation of sound power level
Power unit noise
Tyre/road noise
V :Vehicle speed [km/h]
V0 :Reference vehicle speed (=1km/h)
B0, B1:Regression coefficient
N :Engine speed [rpm]
N0 :Reference engine speed (=1rpm)
T :Engine load [%]
A0~A2:Regression coefficient
= 0+ 1 log10
0+ 2
= 0 + 1 log10𝑉
𝑉0
LA
W,E
[dB
]
N [rpm]
T = 10 %
T = 100 %
LW
A,T
[dB
]
V [km/h]
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Running condition and radiated sound power level
Change of engine speed and vehicle
speed obtained as a output of traffic flow
model
Time [s]
Engine speed
Vehicle speed
Sou
nd
po
we
r le
vel [
dB
(A)]
Time [s]
Power unit noise
Tyre/road noise
Total
Running conditions
Sound power level
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Calculated sound power levels based on
the running condition above and sound
power level equations
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Sound propagation from vehicles to sound receiving point
sound receiving point
Sound propagation
50
60
70
80
90
1200 1300 1400 1500 1600 1700 1800
A特性音圧レベル[dB]
時間 [s]
0 100 200 300 400 500 600
A-w
eig
hte
d S
PL
[d
B]
Time [s]
Sound level at the sound receiving point is calculated by summing up the
sound propagates from all vehicles. By repeating such calculations over
time, fluctuations in road traffic noise can be obtained.
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Predicted result of road traffic noise
Calculation of LAeq
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60
70
80
90
1200 1300 1400 1500 1600 1700 1800
A特性音圧レベル[dB]
時間 [s]
0 100 200 300 400 500 600
Time series fluctuation of sound level at sound receiving point
traffic light:GreenA
-we
igh
ted
SP
L [d
B]
Time [s]
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Setting for estimating the effect of tightening limit value
Lurban [dB]
Fre
qu
en
cy [%
]
Distribution of Lurban LE (Power unit noise) + LT (Tyre/road noise)
LE [dB] LT [dB]
Engine speed N [rpm]
LW
A,E
[dB
]
Limit Reduction Reduction
Power unit noise
= 0 + 1 log10
0+ 2
Tyre/road noise
Vehicle speed V [km/h]
LW
A,T
[dB
] = 0 + 1 log10
𝑉
𝑉0
The values and frequency of the coefficients A0 and B0 are
set according to the level distribution of each sound source;
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Road traffic noise estimation
-- Validation of calculation results
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Validation: Comparison of measured and calculated LAeq
The coefficients of tyre road noise on
several types of road surfaces were set
based on the relationship between vehicle
speed and pass-by noise measured on
public roads.
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References
1) Y. Oshino, K. Tsukui and H. Tachibana, "Prediction of road traffic noise taking account of
transient running conditions of vehicles -Part 1. Relationships between running
conditions and noise radiation-," J. Acoust. Soc. Jpn. (J), 50, pp. 205-214 (1994) (in
Japanese).
2) Y. Oshino, K. Tsukui and H. Tachibana, "Prediction of road traffic noise taking account of
transient running conditions of vehicles -Part 2. Simulation of traffic flow and calculation
of noise propagation-," J. Acoust. Soc. Jpn. (J), 50, pp. 977-985 (1994) (in Japanese).
3) K. Tsukui, Y. Oshino, G. van Blokland and H. Tachibana, "Study of the road traffic noise
prediction method applicable to low-noise road surfaces," Acoust. Sci. & Tech. 31, 1,
pp. 102-112 (2010).
4) T. Suzuki, Y. Oshino and H. Tachibana, "Road traffic prediction model around
intersection taking account of right- and left- turn traffic," J, Acoust. Soc. Jpn. (J), 60,
pp. 526-535 (2004) (in Japanese).
5) T. Suzuki, K. Tsukui, Y. Oshino and H. Tachibana, "Road traffic prediction model around
signalized intersections," Proc. Inter-noise 2003, pp. 1870-1873 (2003).
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