femethods.reactions module

The reactions module defines different reaction classes

A reaction is required to support an element to resist any input forces.

There are two types of reactions that are defined.

• PinnedReaction, allows rotational displacement only
• FixedReaction, does not allow any displacement

class femethods.reactions.FixedReaction(location: float)

Bases: femethods.reactions.Reaction

A FixedReaction does not allow any displacement or change in angle

A FixedReaction resists both force and moments. The displacement and the angle are both constrained and must be zero at the reaction point. FixedReactions are typically applied at the ends of a Beam.

Parameters:location (float) – the axial location of the reaction along the length of the beam

name

short name of the reaction (fixed). Used internally

Type:str

Warning

The name attribute is used internally. Do not change this value!

name = 'fixed'

class femethods.reactions.PinnedReaction(location: float)

Bases: femethods.reactions.Reaction

A PinnedReaction allows rotation displacements only

A PinnedReaction represents a pinned, frictionless pivot that can resist motion both normal and axial directions to the beam. It will not resist moments. The deflection of a beam at the PinnedReaction is always zero, but the angle is free to change

Parameters:location (float) – the axial location of the reaction along the length of the beam

name

short name of the reaction (pinned). Used internally

Type:str

Warning

The name attribute is used internally. Do not change this value!

name = 'pinned'

class femethods.reactions.Reaction(location: float)

Bases: femethods.core._common.Forces

Base class for all reactions

The Reaction class defines general properties related to all reaction types.

Parameters:location (float) – the axial location of the reaction along the length of the beam.

Note

Any force or moment values that where calculated values are invalidated (set to None) any time the location is set.

force

the force of the reaction after it has been calculated

Type:float | None

moment

The moment of the reaction after it has been calculated

Type:float | None

boundary

invalidate() → None

Invalidate the reaction values

This will set the force and moment values to None

To be used whenever the parameters change and the reaction values are no longer valid.

location

Location of the reaction along the length of the beam

The units of the length property is the same as the units of the beam length.

The value of the location must be a positive value that is less than or equal to the length of the beam, or it will raise a ValueError.

Note

The force and moment values are set to None any time the location is set.

name = ''

value

Simple tuple of force and moment

Returns:tuple (force, moment)