Track interaction spring > Input Parameters

Definition and modification of the stiffness parameters of "track interaction springs" (STrack)

"Track interaction springs" are complex spring elements, where the constitutive relation of the shear terms (strains in local y and z direction) is variable (slope Cy, Cz) and bi-linear (shear forces limited to a prescribed maximum value). A linear relationship governs the strain in x-direction (Cx = constant). The rotational stiffness terms are variable but linear (without upper limit).

Setting

Description

From/To/Step

Element series, for which the section properties are input/modified.

Element type

Track interaction spring. An other element type can be selected by pressing the arrow . According the chosen element type the input pad will be changed

Aero class / EccType

Irrelevant in this context

Spring constant for the strain in local x direction. This value is constant, i.e. the stress-strain relationship for the local x-direction is linear

Limit force for distinguishing between the case "Unloaded" and "Loaded".

Setting	Description
Unloaded	means Fx < 0.0 if F > 0.0, or Fx > 0.0 if F < 0.0 respectively
Loaded	means Fx > 0.0 if F > 0.0, or Fx < 0.0 if F < 0.0 respectively

If the actual force Fx is between 0.0 and F, the spring constants and shear force limits

will be linearly interpolated. No "Loaded" case exists when F = 0.0. In this case, the values for "Unloaded" are taken regardless of the current Fx value.

Unloaded

Setting	Description
Cy, Cz	Spring constants for the shear strain for the case "Unloaded" acc. to the above definition.
CMx, CMy, CMz	Spring constants for the rotations for the case "Unloaded" acc. to the above definition.
Fy, Fz	Shear force limits (absolute value) for for the case "Unloaded" acc. to the above definition Default (Fy or Fz = 0.0): Shear force not limited

Loaded

Setting	Description
Cy, Cz	Spring constants for the shear strain for the case "Loaded" acc. to the above definition.
CMx, CMy, CMz	Spring constants for the rotations for the case "Loaded" acc. to the above definition.
Fy, Fz	Shear force limits (absolute value) for for the case "Loaded" acc. to the above definition Default (Fy or Fz = 0.0): Shear force not limited