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Are you sure that it is not an unstable system when you have hinges at the member ends? Yes, sir, I have to attach an additional system having rigid links that are free to rotate at the joint to the main beam through nodes 2 and 3. I even want a rigid link that is connected to another rigid link bu...

Tcl performs integer division. set L 12 puts [expr $L/4] will produce zero. Your nodes are all at zero coordinate. So, either set L 12.0 or divide by 4.0 That is not the problem sir, I have checked. My eigenvalue analysis and simple transient analysis without the rigid links run successfully, so I ...

You don't have all the DOFs properly restrained. Probably missing something in the equalDOF command. Dear Sir, Thanks for the reply. I am attaching the desired code herewith. I wanted to make the connection of rigid link with the Beam structure as hinged i.e. nodes 2 and 3 with the rigid links as c...

Hi, I am getting the following error when i run the transient analysis for a structure consisting of rigid links that are joined by hinges. BandGenLinLapackSolver::solve() -factorization failed, matrix singular U(i,i) = 0, i= 1. For making hinge i have used equalDOF command by introducing additional...

selimgunay wrote: ↑

Wed Jun 23, 2021 9:01 am

There is no built-in command. You can try modeling it with translation and rotation springs.

Dear Sir. Can you briefly write, how exactly i can use rotational spring to model the gear of some diameter?

I wanted to amplify the deflection at a node by using the gear-pinion-rack system in OpenSees. Are there any inbuilt commands that I can use to model it? Please suggest some ideas.

Thanks.

selimgunay wrote: ↑

Fri Jun 18, 2021 12:23 pm

You can try use a hysteretic material to define the force-deformation of your spring: https://opensees.berkeley.edu/wiki/inde ... c_Material

Thankyou sir.

mhscott wrote: ↑

Wed Jun 16, 2021 6:17 am

What you are asking is unclear.

Sir, I have modified my previous post.

I can implement a cylindrical spring which is simple linear by using the command ''uniaxialMaterial Elastic 1 $ks'', where $ks is the single specified stiffness of the linear spring. I need to implement a conical spring which will be multilinear with a different set of $ks1, $ks2, $ks3, etc at diffe...