Ground surfaces¶
NoiseModelling is a tool for producing noise maps. To do so, at different stages of the process, the application needs input data, respecting a strict formalism.
Below we describe the table GROUND
, dealing with the land use type, with an associated ground absorption coefficient (G).
The other tables are accessible via the left menu in the Input tables
section.

Table definition¶
Warning
In the lists below, the two columns are mandatory
THE_GEOM
- Description: 2D geometry of the surfaces (
POLYGON
orMULTIPOLYGON
) - Type: Geometry
- Description: 2D geometry of the surfaces (
G
- Description: acoustic ground’s absorption (from
0
: very hard to1
: very soft - see table below) - Type: Double
- Description: acoustic ground’s absorption (from
Description | G |
---|---|
Very soft (snow or moss‐like) | 1 |
Soft forest floor (short, dense heather‐like or thick moss) | 1 |
Uncompacted, loose ground (turf, grass, loose soil) | 1 |
Normal uncompacted ground (forest floors, pasture field) | 1 |
Compacted field and gravel (compacted lawns, park area) | 0.7 |
Compacted dense ground (gravel road, car park) | 0.3 |
Hard surfaces (most normal asphalt, concrete) | 0 |
Very hard and dense surfaces (dense asphalt, concrete, water) | 0 |
Topology¶
At a given point, there can only be one value of G. Consequently, in the GROUND
table, the geometries must not overlap.