Railways

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 are described the tables RAIL_SECTIONS and RAIL_TRAFFIC.

The other tables are accessible via the left menu in the Input tables & parameters section.

_images/rails_banner.png

Warning

In the lists below, the columns noted with * are mandatory

Railways sections

  • Table name : RAIL_SECTIONS

  • Description: contains all the sections of railways

Table definition

  • THE_GEOM *

    • Description: Railway’s geometry

    • Type: Geometry (LINESTRING or MULTILINESTRING)

  • IDSECTION *

    • Description: A section identifier (PRIMARY KEY)

    • Type: Integer

  • NTRACK *

    • Description: Number of tracks

    • Type: Integer

  • TRACKSPD *

    • Description: Maximum speed on the section (in km/h)

    • Type: Double

  • TRANSFER
    • Description: Track transfer function identifier

      • 1 = Mono-bloc sleeper on soft rail pad

      • 2 = Mono-bloc sleeper on medium rail pad

      • 3 = Mono-bloc sleeper on stiff rail pad

      • 4 = Bi-bloc sleeper on soft rail pad

      • 5 = Bi-bloc sleeper on medium rail pad

      • 6 = Bi-bloc sleeper on stiff rail pad

      • 7 = Wooden sleeper (Traverse en bois)

    • Type: Integer

  • ROUGHNESS
    • Description: Rail roughness identifier

      • 1 = Classic lines

      • 2 = TGV (for France) lines

    • Type: Integer

  • IMPACT
    • Description: Impact noise coefficient identifier

      • 0 = No impact

      • 1 = Single joint, switch or crossing per 100 m

    • Type: Integer

  • CURVATURE
    • Description: Section’s curvature identifier

      • 0 = R > 500 m

      • 1 = 300 m < R < 500 m

      • 2 = R < 300 m

    • Type: Integer

  • BRIDGE
    • Description: Bridge transfer function identifier

      • 0 = Any type of track or bridge except metal bridges with unballasted tracks

      • 1 = Metal bridges with unballasted tracks + 5dB

    • Type: Integer

  • TRACKSPC

    • Description: Commercial speed on the section (in km/h)

    • Type: Double

  • ISTUNNEL

    • Description: Indicates whether the section is a tunnel or not (0 = no / 1 = yes)

    • Type: Boolean

Geometry modelling

The modeling of the geometry is identical to the road’s one (see “Roads” page). The only difference is that the affected height is not 5cm by default. It depends on the model used (e.g in CNOSSOS: rolling noise = 0.05m / aerodynamic noise = 4m ).

Railways traffic

  • Table name : RAIL_TRAFFIC

  • Description: contains all the railways traffic

Table definition

  • IDTRAFFIC *

    • Description: A traffic identifier (PRIMARY KEY)

    • Type: Integer

  • IDSECTION *

    • Description: A section identifier, refering to RAIL_SECTIONS table

    • Type: Integer

  • TRAINTYPE *
  • TRAINSPD *

    • Description: Maximum train speed (in km/h)

    • Type: Double

  • TDAY

    • Description: Hourly average train count, during the day (6-18h)

    • Type: Integer

  • TEVENING

    • Description: Hourly average train count, during the evening (18-22h)

    • Type: Integer

  • TNIGHT

    • Description: Hourly average train count, during the night (22-6h)

    • Type: Integer