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hi everyone i used nonlinear beam elements to model a frame, i want to get the moment curvature of a column. i think there are two ways to get the moment and curvature 1 recorder the section(integration point) force and deformation of the column, i can get the moment and curvature, respectively. 2 u...

the difference of the periods should be very small, i think it is normal.

hi i am using the Limit State Material , the command is: uniaxialMaterial LimitState $matTag $s1p $e1p $s2p $e2p $s3p $e3p $s1n $e1n $s2n $e2n $s3n $e3n $pinchX $pinchY the corresponding website is following: http://opensees.berkeley.edu/wiki/index.php/Limit_State_Material i am using the Limit State...

your materaial uniaxialMaterial Elastic 12 0. which means there is no restrains at the direction. so the matrix is singular. you can try a proper value for the rotation matrerial or you can set a very big value. Have a try and good lucn.

hi everyone i am using the penalty method constraints Penalty $alphaS $alphaM could anyone tell me how to determine the reasonable values for Penalty factors $alphaS $alphaM. my model used "equalDof command ", i used the values( $alphaS=10e14, $alphaM10e14) , but it seems give wrong answers. thank y...

hello everyone: when i do a time history analysis, i used the modal analysis command(eigen <$type> <$solver> $numEigenvalues) to compute the omega^2 in every time step, and update the damping ratio in every step(use this command:rayleigh $alphaM $betaK $betaKinit $betaKcomm), the frequency is needed...

sabir wrote: > hi all > i'm new user of opensees. i want to calculate the plastic hing rotation or > maximum theta in ends of beams or calumns, to calculation the rotation > ductility. but i dont now what command i have to use? > please explain the basicdeformation command? > and does opensees only ...

linguan118 wrote: > You mean the force of the zero-length element? I mean the capacity of the Axial limit curve, the Axial limit curve will change during dynamic analysis, so the axial capacity of the Zero-Length Element will change, I want to get the axial capacity during dynamic analysis. another ...

I use a Zero-Length Element with LimitState materials in a model .
Shear LimitCurve and Axial LimitCurve are used in the model. I want to get the axial capacity of the Zero-Length Element during analysis.
which command should i used? Thanks and best wishes.

you can recorder a node's damping force
recorder Node -file DampingForce.out -time -node 2 -dof 1 rayleighForces

hi everyone:
I saw a recorder command used to recorder a beam element's rotation, what the roataion of a beam element stands for? thank you
recorder Element -file $dataDir/elerotbasic.out -time -ele 1 rotation

I read this website about LimitStateMaterial , http://opensees.berkeley.edu/wiki/index.php/CenterCol_basicModel_Dynamic.tcl but I can not understand why a soft spring is used here? Thank you. #soft spring to take axial load after failure uniaxialMaterial Elastic $softMatTag 99.9 element zeroLength 4...

vesna wrote:
> It is the unbalanced load.
Thanks for your prompt reply vesna.

hi vesna, the folowing is model you built before could you tell me what is the reaction of node 2 ? if I recorder the reaction of node 1, i know the reaction of node 1is the support reaction,but what the reaction of node 2(a free node ) stand for? Thanks # Canilever column from Chopra's book (Exampl...

hi everyone: how to considering the coupling of flexure and shear in beam element, here is what i use in a model, is it right? i use limitState materials and ZeroLength elemen to consider coupling of flexure and shear in beam element, the shear failure will occur when the total deformation (shear de...