spring

[cyw]

I want to define a spring with a angle,that is to say the spring is not in horizontal or vertical direction.But the zeroLength element has the direction of "-dir 1 2".What could I do?

[fmk]

you could use a truss instead and add the second node inclined to the first.

[cyw]

Thank you,fmk.Another question now,it is about the load .I want to apply a node force,but it shows errors. I find the same problem in this forul, but I could not solve it with that method.

laod commad is :

pattern Plain 1 Constant {
load 447 0 40
}

error message is :

WARNING bad command - want: load nodeId 3 forces
Input command: load 447 0 40
WARNING - error reading load pattern information in { }

[fmk]

as the message says its looking for 3 forces after the nodeTag .. you only provide 2!

[cyw]

My model contains nodes with 2dofs and 3dofs.I want to apply load to the node with 2dofs.If the command is "load 447 0 40 0",then it shows error message as "Node::addunbalLoad - load to add of incorrect size 3 should be 2" .It is OK during the gravity application stage,do you think is it possible that there is something wrong with my model?

[cyw]

Dear fmk,I have found the problems. If I build model with 2dof first, then the 3dof , I have to apply load to nodes with 3dofs. I build model with 3dofs first, then it is OK to apply load to nodes with 2dof.


model BasicBuilder -ndm 2 -ndf 2
source tunnel2.tcl
source viscous2.tcl
model BasicBuilder -ndm 2 -ndf 3
source soil2.tcl
source couple.tcl
It failed to apply load on node 447(node 447 has 2 dofs)

model BasicBuilder -ndm 2 -ndf 3
source soil2.tcl
model BasicBuilder -ndm 2 -ndf 2
source tunnel2.tcl
source viscous2.tcl
source couple.tcl
It is OK to apply load on node 447

[fmk]

that works .. you could also use the model command again.