The Effects of Pavement Properties on Road Tire Noise
Wing-tat HUNG, Wing-gun WONG
Chung-fai NG, Chi-ho YIM
The Hong Kong Polytechnic University
Introduction
Factors affecting Pavement Noise:• Method of measurement
• Mobilized measurement methods: trailer and on-board microphone
• Stationary measurement methods: coast-by, controlled pass-by and statistical pass-by
Pavement type and thicknessSurface texture and aggregate sizeTraffic speedFrequency range
Trailer and Pass-By Method
On-board Microphone Method
On-board Measurement microphone locations
On-board Measurement Method with skirting
Our Modified Close Proximity Method
Detailed Equipment Set-up
Site No. Location Type of Pavement Age of Pavement Surface Thickness
1a Island Eastern CorridorBetween A Kung Ngam Road and Heng Fa Chuen(From A Kung Ngam to Lei Yue Mun Banack)
Porous friction course (PFC)
June 1998 30 mm thick friction course on 20 mm thick cushion course
1b Island Eastern CorridorBetween A Kung Ngam Road and Heng Fa Chuen(From Lei Yue Mun Banack to Heng Fa Chuen)
Polymer modified friction course (PMFC)
April 2001 i.30 mm thick friction course on 20 mm thick cushion courseii.30 mm thick friction course on 40 mm thick wearing course
2 Island Eastern CorridorFrom Oil Street to Tin Chui Street
Polymer modified friction course (PMFC)
April 1998 30 mm thick friction course on 20 mm thick cushion course
3 Island Eastern CorridorFrom Sai Wan Ho Slip Road to Tai Hong Street
Polymer modified friction course (PMFC)
November 2000 i.30 mm thick friction course on 40 mm thick wearing courseii.45 mm thick wearing course only
4 Kwun Tong BypassFrom Wai Yip Street to Shing Yip Street
Bridge deck overlaid with asphalt (BDOA)
2001 N.A.
5 Kwun Tong RoadFrom Choi Wan Road to Ping Shek Estate
Concrete overlaid with asphalt (PCC)
1999 N.A.
6 Kwun Tong RoadFrom Yan Wing Building to Telford Garden Block U1
Asphalt (Bituminous pavement, ABP)
2001 N.A.
7 Lai Chi Kok Bay BridgeFrom Ching Lai Court to Mei Fu Sun Chuen
Bridge deck overlaid with asphalt (BDOA)
2001 N.A.
8 Lung Cheung Road (Diamond Hill)From Hammer Hill Road to Po Kong Village Road
Concrete overlaid with asphalt (PCC)
1999 N.A.
9 Lung Cheung Road (Wong Tai Sin)From Po Kong Village Road to Fung Mo Street
Stone Mastic Asphalt (SMA)
1999 N.A.
10 Princess Margaret Road From Chatham Road South to Wylie Road
Concrete overlaid with asphalt (PCC)
1999 N.A.
11 Tolo Highway From Tai Po Kiu to Ma Liu Shui
Polymer modified friction course (PMFC)
March 2001 30 mm thick friction course on 40 mm thick wearing course
12 Tuen Mun RoadFrom Siu Lam to Tai Lam
Porous friction course (PFC)
1999 N.A.
13 Tuen Mun RoadFrom Ting Kau to Chai Wan Kwok
Porous friction course (PFC)
1999 N.A.
14 Western Kowloon Corridor From Tonkin Street to Cheung Sha Wan
Bridge deck overlaid with asphalt (BDOA)
2001 N.A.
15 Western Kowloon Expressway From Tonkin Street to Olympic Center
Bridge deck overlaid with asphalt (BDOA)
1997 N.A.
Selected Pavements for Noise Measurements
0
10
20
30
40
50
60
70
80
90
100
2531
.5 40 50 63 8010
012
516
020
025
031
540
050
063
080
010
0012
5016
0020
0025
0031
5040
0050
0063
0080
00
1000
0
Frequency Band (Hz)
dB
(A)
Sound at Source Sound at end of left tube Sound at end of right tube
Sound Level Calibration
Site No. Type of Pavement Year of Construction
Leq (dBA)
50 km/h 70 km/h 100 km/h
1a Porous friction course June 1998 99.1 100.6 ---
1b (i) Polymer modified friction course April 2001 97.8 96.1 ---
1b (ii) Polymer modified friction course April 2001 92.7 99.5 ---
2 Polymer modified friction course April 1998 101.1 104.7 ---
3 (i) Polymer modified friction course November 2000 97.5 --- ---
3 (ii) Polymer modified friction course November 2000 96.9 --- ---
4 Bridge deck overlaid with asphalt 2001 98.1 97.8 ---
5 Concrete overlaid with asphalt (PCC) 1999 102.1 108.2 ---
6 Asphalt (Bituminous pavement) 2001 96.1 102.7 ---
7 Bridge deck overlaid with asphalt 2001 94.9 100.5 ---
8 Concrete overlaid with asphalt (PCC) 1999 103.6 --- ---
9 Stone Mastic Asphalt (SMA) 1999 98.3 100.9 ---
10 Concrete overlaid with asphalt (PCC) 1999 100.5 106.1 ---
11 Polymer modified friction course March 2001 96.7 97.8 104.4
12 Porous friction course 1999 99.2 102.8 ---
13 Porous friction course 1999 98.8 101.7 ---
14 Bridge deck overlaid with asphalt 2001 96.3 102.0 ---
15 Bridge deck overlaid with asphalt 1997 98.0 101.3 105.0
The Pavement Tire Noise Measured Levels
Rank Site No.
Type of Pavement Year of Construction
Leq (dBA) Difference Relative to Reference
(dBA)
1 1b (ii) Polymer modified friction course April 2001 92.7 -6.3
2 7 Bridge deck overlaid with asphalt 2001 94.9 -4.1
3 6 Asphalt (Bituminous pavement) 2001 96.1 -2.9
4 14 Bridge deck overlaid with asphalt 2001 96.3 -2.7
5 11 Polymer modified friction course March 2001 96.7 -2.3
6 3 (ii) Polymer modified friction course November 2000 96.9 -2.1
7 3 (i) Polymer modified friction course November 2000 97.5 -1.5
8 1b (i) Polymer modified friction course April 2001 97.8 -1.2
9 15 Bridge deck overlaid with asphalt 1997 98.0 -1.0
10 4 Bridge deck overlaid with asphalt 2001 98.1 -0.9
11 9 Stone Mastic Asphalt (SMA) 1999 98.3 -0.7
12 13 Porous friction course 1999 98.8 -0.2
13 1a Porous friction course June 1998 99.1 0.1
14 12 Porous friction course 1999 99.2 0.2
15 10 Concrete overlaid with asphalt (PCC) 1999 100.5 1.5
16 2 Polymer modified friction course April 1998 101.1 2.1
17 5 Concrete overlaid with asphalt (PCC) 1999 102.1 3.1
18 8 Concrete overlaid with asphalt (PCC) 1999 103.6 4.6
Reference pavement (Average of all porous friction course pavements
99.0
Ranking of pavement surfaces based on measured Leq at 50kph
Rank Site No. Type of Pavement Year of Construction
Leq (dBA) Difference Relative to Reference (dBA)
1 1b (i) Polymer modified friction course April 2001 96.1 -5.6
2 11 Polymer modified friction course March 2001 97.8 -3.9
3 4 Bridge deck overlaid with asphalt 2001 97.8 -3.9
4 1b (ii) Polymer modified friction course April 2001 99.5 -2.2
5 7 Bridge deck overlaid with asphalt 2001 100.5 -1.2
6 1a Porous friction course June 1998 100.6 -1.1
7 9 Stone Mastic Asphalt (SMA) 1999 100.9 -0.8
8 15 Bridge deck overlaid with asphalt 1997 101.3 -0.4
9 13 Porous friction course 1999 101.7 0.0
10 14 Bridge deck overlaid with asphalt 2001 102.0 0.3
11 6 Asphalt (Bituminous pavement) 2001 102.7 1.0
12 12 Porous friction course 1999 102.8 1.1
13 2 Polymer modified friction course April 1998 104.7 3.0
14 10 Concrete overlaid with asphalt (PCC) 1999 106.1 4.4
15 5 Concrete overlaid with asphalt (PCC) 1999 108.2 6.5
Reference pavement (Average of all porous friction course pavements)
101.7
Ranking of pavement surfaces based on measured Leq at 70kph
0.0
20.0
40.0
60.0
80.0
100.0
120.0
25
31
.5 40
50
63
80
10
0
12
5
16
0
20
0
25
0
31
5
40
0
50
0
63
0
80
0
1k
1.2
5k
1.6
k
2k
2.5
k
3.1
5k
4k
5k
6.3
k
8k
10
k
Frequency (Hz)
So
un
d L
ev
el (
dB
A)
Avg all PFC Site 1bii - PMFC Site 8 - PCC
Comparison of sound spectrums for pavements at 50 kph
0.0
20.0
40.0
60.0
80.0
100.0
120.0
25
31
.5 40
50
63
80
10
0
12
5
16
0
20
0
25
0
31
5
40
0
50
0
63
0
80
0
1k
1.2
5k
1.6
k
2k
2.5
k
3.1
5k
4k
5k
6.3
k
8k
10
k
Frequency (Hz)
So
un
d L
ev
el (
dB
A)
Avg all PFC Site 1bi - PMFC Site 5 - PCC
Comparison of sound spectrums for pavements at 70 kph
0.0
20.0
40.0
60.0
80.0
100.0
120.0
25
31.5 40 50 63 80 100
125
160
200
250
315
400
500
630
800 1k
1.25
k
1.6k 2k
2.5k
3.15
k 4k 5k
6.3k 8k 10k
Frequency (Hz)
Soun
d Le
vel (
dBA
)
Site 1bi - 2 yr PMFC Site 2 - 5 yr PMFC Site 1a - 5 yr PFC
Comparison of sound spectrums for Friction Courses at 70 kph
Site No.
Age of Pavement
Surface ThicknessEquivalent Noise Level Leq (dBA)
Difference from Average (dBA)
1bi Apr 200130 mm thick friction course on 20 mm thick
cushion course96.1 -3.4
1bii Apr 200130 mm thick friction course on 40 mm thick
wearing course99.5 0.0
2 Apr 199830 mm thick friction course on 20 mm thick
cushion course104.7 5.2
11 Mar 200130 mm thick friction course on 40 mm thick
wearing course97.8 -1.7
Average 99.5
Comparison of Leq with different surface thickness at 70kph
Rank Type of Pavement Year of Construction Leq (dBA)
1 Polymer modified friction course 2001 95.7
2 Asphalt (Bituminous pavement) 2001 96.1
3 Bridge deck overlaid with asphalt 2001 96.4
4 Polymer modified friction course 2000 96.9
5 Bridge deck overlaid with asphalt 1997 98.0
6 Stone Mastic Asphalt (SMA) 1999 98.3
7 Porous friction course 1999 99.0
8 Porous friction course 1998 99.1
9 Polymer modified friction course 1998 101.1
10 Concrete overlaid with asphalt (PCC) 1999 102.1
Conclusions
At 50 kph
Rank Type of Pavement Year of Construction Leq (dBA)
1 Polymer modified friction course 2001 97.8
2 Bridge deck overlaid with asphalt 2001 100.1
3 Porous friction course 1998 100.6
4 Stone Mastic Asphalt (SMA) 1999 100.9
5 Bridge deck overlaid with asphalt 1997 101.3
6 Porous friction course 1999 102.3
7 Asphalt (Bituminous pavement) 2001 102.7
8 Polymer modified friction course 1998 104.7
9 Concrete overlaid with asphalt (PCC) 1999 107.2
Conclusions
At 70 kph
Major Findings:
1. Pavement surface type has signifiant impacts on pavement tire noises
2. The equivalent noise levels Leq for all test pavements increased with vehicle speed
3. Sound levels for two-year-old PMFC pavements did not increase significantly while there were increases in sound level of 2.1 dBA and 3.0 dBA for the five-year-old pavement at speed of 50 km/h and 70 km/h respectively
Major Findings:
4. The PMFC pavements provide the most significant reduction in equivalent noise levels.
5. The highest equivalent noise level Leq was recorded at the PCC pavements.
6. A 20 mm thick PMFC pavement provides a reduction in sound levels by as much as 3.4 dBA in Leq.
END. Thank you