New element

[mehdi12345]

hi dr silvia
is there any way to define a new element using existing elements ???
i mean like beamWithHinges or TrussElement they are just another definition for existing elemets that mixed in way that serve a new purpose,
how can I do it???
Thanx

[vesna]

Yes, you can create new element by modifying the existing one. In the OpenSees source code you can find routine for existing elements.

Here is the link on instructions how to add new element to OpenSees:
http://opensees.berkeley.edu/wiki/index ... _Developer

[mehdi12345]

thanx for your answer, but i want to combine two elements. for example if i combine an elastic material with a zero length element that frees rotational degree of freedom then i will have a truss element. i want to do sth like this.
thanx for your help

[silvia]

you can put elements in series (share one node, have the same force and the displacements/flexibilities add up) or in parallel (share two nodes, have the same displacements and the forces/stiffnesses add up).

[mehdi12345]

thanx for ur answer
but i want to use elements in series , for example a nonlinear beam column with 3 hinges in begining, middle and end of it. i want to have it as just one element. that when i define it between two nodes and defining parameters of section and hinges, i define it at once, the whole package has just one element tag and no need to define extra nodes and elements
how can i do it?

[silvia]

you can do it if you go into the code.
in tcl, you have to just do it as many elements.

[mehdi12345]

thanx for your answer
could u please put a link of an example here, so i can use it as a tutorial
regards