Date post: | 07-Jan-2017 |
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EnviroSHaPER Noise ModelDavid Morley, Imperial College London
EnviroSHaPER Noise Model
Generate noise exposure at points (addresses)
User-friendly application
Based on the new CNOSSOS-EU standard model
Simplified approach for national scales
Noise exposure
Noise exposure
Common metrics used in epidemiology
LAEQ16 16hr day average 07:00 – 23:00
LDAY 12hr day average 07:00 – 19:00
LEVE 4hr evening average 19:00 – 23:00
LNIGHT 8hr night average 23:00 – 07:00
LDEN 24hr average weighted towards night and evening
CNOSSOS-EU Framework
A harmonised method for Europe to allow comparison between countries
Rail, Aircraft, Industrial and Road sources
A full (complex) sound propagation model to assign noise levels to receptors
In this application, both source definition and propagation needs to be simplified
EnviroSHaPER Input Data
Data set Description Use
Traffic flow Number of vehicles per hour on a road segment On a particular road segment, the number of vehicles defines the total noise source
Vehicle type Relative proportion of light vehicles (e.g. passenger cars) and heavy vehicles (e.g. lorries, buses)
A heavy vehicle contributes more noise than a light vehicle
Speed limits Maximum legal limit or average speed (if available) according to road class and vehicle type
The speed of a vehicle effects the associated sound power output
Road network Spatial layout of the road network Sound propagation and contribution at a receptor is based on the distance to, and the number of nearby roads and associated traffic flows
Road junction type Presence of roundabouts or crossings on a road segment
Influence on acceleration and deceleration and vehicle engine noise
Land cover Land cover types over the study area (buildings, grassland, woodland, water bodies etc.)
Distinction between sound absorbent (e.g. vegetation) and sound reflective surfaces (e.g. concrete)
Building heights Height and location of buildings Buildings act as a barrier to sound propagationAir temperature Annual average air temperature As air temperature increases, traffic noise will decrease
Prevailing wind direction Expected proportion of time wind can be expected from a certain direction (by quadrant)
A favourable (following) wind direction can aid sound propagation
Road surface type and age Road surface material (e.g. concrete, asphalt) and age (condition)
Older roads and specific surface types lead to higher rolling noise levels
Studded tyre usage Relative proportion of vehicles using studded (snow) tyres
Studded tyre use contributes to higher rolling noise levels
Road gradient Slope of each road segment Influence on acceleration and deceleration and vehicle engine noise
Topography Elevation model of the study area Line-of-sight between noise sources and receivers for sound propagation
EnviroSHaPER Input Data
Land coverBuilding heightsRoad geographyTraffic flow
EnviroSHaPER Input Data
Morley, D.W., de Hoogh, K., Fecht, D., Fabbri, F, Bell, M. , Goodman, P.S., Elliott, P., Hodgson, S., Hansell, A., and Gulliver, J. International scale implementation of the CNOSSOS-EU road traffic noise prediction model for epidemiological studies (in press) Environmental Pollution
EnviroSHaPER Modelling
For each receptor point:
1) Find road segments within 500m2) Project source-receptor ‘ray paths’3) Calculate source noise at these points4) Calculate propagation of noise along ray
path to receptor5) Exponentially sum values for each path
EnviroSHaPER Modelling
Source traffic noise
DATA SOURCES•Road network geography •Traffic flow for light and heavy vehicles
SOUND POWER EMMISION•Rolling noise: Road surface (type, age)•Propulsion noise: Engine noise (road gradient, vehicle speed), vehicle type
EnviroSHaPER Modelling
Sound propagationNoise levels at a receptor is the accumulation of noise along all propagation paths
Propagation is a function of:Distance from the sourceAngle of view of to the road segmentAtmospheric absorptionMeteorological conditions Land cover
EnviroSHaPER Modelling
Sound propagation
EnviroSHaPER Application
A user-friendly windows interfaceRuns in PostGIS behind the scenes
EnviroSHaPER Application
Dialogue boxes to specify inputsAll inputs ArcGIS shapefiles
Very few other options
EnviroSHaPER ApplicationReceptors CORINE polygons
Generalised building heights
Road network and traffic flow
EnviroSHaPER Application
As each receptor is processed:Noise estimations shownMap of roads in range
• At the end:Histogram of predictionsClickable points on OSM base
Summary
CNOSSUS-EU model designed to allow comparable noise models for EuropeIs extremely detailed (localised), but here is simplified to more general (regional) situations.
ImplementationUser-friendly front-end to a PostGIS spatial data baseRequires PostGIS is installed (but runs behind the scenes)Output is ArcGIS shapefile and .csv for Excel
See the User Guide for full detailsDavid Morley: [email protected]
Acknowledgement
The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 261433 (Biobank Standardisation and Harmonisation for Research Excellence in the European Union - BioSHaRE-EU)