Title: Low noise road surfaces : current practices in Europe
1Low noise road surfaces current practices in
Europe
2nd Workshop Brussels, 24 march
2009 Recommendations for future harmonised
European policies
Fabienne Anfosso-Lédée LCPC, France
2Noise in TYROSAFE
TYROSAFE Tire and Road Surface Optimisation for
Skid Resistance and Further Effects
3Noise an environmental problem
EC Green Paper on Future Noise Policy, 1996
- 20 of EU population (80 M) exposed to
unacceptable noise levels - annual costs caused by noise pollution estimated
between 0.2 and 2 of GPD - Road transport noise is the dominant source (90
of the EC population exposed to noise levels gt 65
dB(A)). - EC regulations of noise sources since the 1970s
- Result limited effect after 25 years
- Traffic growth
- Longer periods of high noise emission
- More roads and spread of built areas etc
4Noise an environmental problem
- EC Directive 2002/49/EC
- Noise mapping for major cities and large
transportation infrastructure gtgt need relevant
noise emission models - Action plans
- gtgt need low noise
- emission solutions
- MS designate competent authorities for drawing
up and adopting maps and action plans - MS set ambient noise limits
5Noise a difficult problem
- National regulations to protect the residents
- Different noise indicators LAeq, Lden, LAmax
- Different legal thresholds
- Different application schemes calculation, check
by measurements - Usually based on noise immission (emission
propagation)
6Road noise emission
Technical
- Different tools to reduce road noise emission
- improve vehicle / tire conception
- Improve road surface conception
- Build noise barriers
- Traffic management speed limits, reduce traffic
volume (re-routing), increase fluidity
7Legislation on road noise emission
8Low noise pavements need for requirements ?
9Tire/Road noise emission
- Tire/road noise mitigation the current practice
in EU
10Measurement methods
Statistical Pass-By (SPB) tire-road noise
measurements
International standard ISO 11819-1 1997
(currently under revision)
1,2 m
7,5 m
Limits... Ø restrictive site conditions Ø spot
measurement
11Characterization of low noise pavements
Close Proximity (CPX) tire-road noise measurements
International standard Pr ISO 11819-2 under
draft Need (a) reference tire(s) Pr ISO
Technical Specification 11819-3 under draft
- need further comparison of devices
- a relationship with SPB is missing
12Low noise road surfaces
- Max range 10 dB(A)
- Effect of
- grading
- porosity
- Important dispersion within a pavement type
SPB French data base, LCPC Strasbourg (Passenger
Cars _at_ 90 km/h and 20C)
13Low noise road surfaces
- Several techniques available
- Porous pavements, single or double layers
- Thin semi-porous layers with small aggregate size
- Rubber asphalts
-
Very Thin AC
Porous AC
Dense A.C.
Expected efficiency in practice 3 5 dB(A)
average benefit of pavement replacement at
initial stage
14Low noise road surfaces
Problem of ageing of acoustic performance of low
noise road surfaces
Example of Porous Asphalt Concrete 0/10 (French
data base)
15Classification of low noise surfaces
It is difficult to compare road surfaces in EU !
- No common names (definition) of pavement products
- No common definition of low noise surfaces
- ? performance indicator RSI (UK), Cwegdek (NL),
Lm25 (D), LCPX (DK, Fin), LAmax (F),LMA (A),
LAeq(24h) (S) - ? classification procedures. Active
classification scheme in 4 countries D, DK, NL,
UK
16Classification of low noise surfaces
EU Members with a noise classification system of
road pavements (results from a questionnaire in
TYROSAFE, set of 15 countries)
17Noise classification procedure
Active systems in 4 European countries
- Germany
- Active since 1981
- Based on CPB/SPB measurements
- Passenger cars _at_120 km/h
- Reference indicator Lm(25) nicht geriffelter
Gussasphalt - Min. 5 sites
- Netherlands
- Based on SPB measurements, 5 m high
- Reference indicator Cwegdek, reference pavement
DAC 0/16 - Car trucks, with different reference speeds
according to roads - Average on 5 worksites if within 2 dB(A)
18Noise classification procedure
- U.K. (HAPAS)
- Based on SPB measurements
- Reference indicator RSI difference between
the traffic noise level calculated from SPB tests
and the theoretical level for the reference
surface - Reference surface newly-laid 20 mm Hot Rolled
Asphalt. - Reference speeds for PC trucks according to
road high speed (110/90 km/h) or medium speed
(80/70 km/h) - Min. 2 sites
- Danemark
- Based on CPX measurements
- 5 classes ranging from A (particularly good) to E
(no noise reduction) - Reference speeds 50 km/h and 80 km/h
19Noise classification procedure
- SILVIA / INQUEST (EU-FP5) classification scheme
- CLASSIFICATION SPB
- texture
- CPX (for SPB spot assessment and further COP
checks) - sound absorption
- COP Check CPX after 2 months
- texture absorption
20COP test procedure
EU members where noise specifications are
introduced in tendering procedures (set of 15)
EU Members where a procedure for COP of acoustic
properties is active (set of 15)
- ? specifications, limits, requirements
- ? indicators
- ? methods for checking CPX, SPB, LAeq
- ? periods of guarantee and ? penalties
21Conclusions
- Measurement methods
- Existing (relative) consensus on 2 methods SPB
and CPX - CPX, SBP, but also proxi method needs to be
further developed and validated - Harmonised Noise Classification of road surfaces
do we need one ? - Harmonised COP test procedure do we need one ?
- How to integrate evolution over time of
performances ?