rolland.components.Ballast

class rolland.components.Ballast(*, sb=[0.0, 0.0], etab=0.0, fresb=[0.0, 0.0], db=[0.0, 0.0])[source]

Bases: object

Ballast Class.

Contains the properties of the ballast.

Caution

Properties of the ballast can either be defined as discrete values acting at the mounting positions or as continuous values acting per meter depending. The values need to be chosen accordingly to the track type.

Parameters:

  • sb (list[float])

  • etab (float)

  • fresb (list[float])

  • db (list[float])

sb

Vertical/lateral ballast stiffness (total value \([N/m]\) or per meter \([N/m^2]\)). Lateral value can be set to zero when lateral rail deflections are omitted.

Type:

list[float], default=[0.0, 0.0]

etab

Ballast loss factor \([-]\).

Type:

float

fresb

Vertical/lateral ballast resonance frequencies \([Hz]\). These frequencies are needed for calculating the viscous damping coefficients if they are not provided. Lateral value can be set to zero when lateral rail deflections are omitted.

Type:

list[float], default=[0.0, 0.0]

db

Vertical/lateral viscous damping coefficient (per meter) \([Ns/m]\). Lateral value can be set to zero when lateral rail deflections are omitted.

Type:

list[float], default=[0.0, 0.0]