Why line load in local coordinate system has only two components?

[Igor76]

Hi
I want to assign line load on beam element in Abaqus.
In Abaqus dialog window Line load has three components in global CS but only two in local CS.
The qwestion is, where is third component and how to assign it?
Thanks in advance

 

[Mustaine3]

The option "Local" refers to the beam orientation, not to a user defined CSYS.


The Users Manual say:
"Use the following option to define a force per unit length in the beam local 1- or 2-direction: ..."

So the missing direction is the one in the direction of the beam itself. How should a outer load in reality act within the beam?
That's why "Local" has only two components.

 

[Igor76]

Like gravity force for example.Any vector in 3d has 3 components.How to put ice load on vertical beam for example?

 

[Mustaine3]

Use the Global option. Gravity is not interested in the beam local orientation. Btw. Gravity is a load type of it's own.
Why do you want an outer force to act exactly within the beam? What would be the equivalent in reality?

 

[Igor76]

In reality I want to put wind and ice loads on my frame.I will use global option of course,because there is no other way.In calculations I need not only behavior of some beam,but behavior of whole system,so I need to put all forces.I hope you understand me,excume for my english

 

[Mustaine3]

Maybe I've misunderstood your post. When you would like to apply the global load in a user defined CSYS, then your question would be valid. This functionality seems to be not available. The user has to recalculate his load in the global directions.

What can be done to help with that recalculation? Define a dummy point load in that local CSYS. Then activate the option for the job that prints out additional model data in the .dat. Do a rightclick at the job in the tree and then Edit. In that menu use the General tab to find that option. After a datacheck you'll find the transformation components in the .dat.

 

[Igor76]

Ok,now when we understood each other my question is still:
where is third component of line load in beam coordinate system?