Ground acoustic

The table ground_acoustic merges the vegetation, water and impervious tables build by GeoClimate. The ground_acoustic table contains an absorption coefficient (g column) to estimate the acoustic energy losses on reflection for a specific surface. Each surface is unique and potential overlaps are eliminated by giving a priority to the input layers. The priorities and the mapping between the type of the input geometries (vegetation, water...) are described in a JSON file.

To compute the ground_acoustic table the following parameters must be set to the workflow configuration file.

"parameters":[
            "noise_indicators":["ground_acoustic":true]
             ]

Below is the schema of the ground_acoustic table.

Name	Type	Constraints	Definition
the_geom	POLYGON	X Y dimension	Geometry
id_ground	SERIAL	not null	Identifier of the ground surface
g	FLOAT		Acoustic absorption coefficient
type	INTEGER		Value allowing to distinguish the type of surface according the input layers
layer	VARCHAR		Name of the input layer