defining moment rotation relation for members
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defining moment rotation relation for members
Hello,
Is there anyway to define the momentrotation relationship for beams and columns. I tried placing 2D rotational springs at the connection points of beams and columns with the joint and assigning the hysteretic material but the damage coefficients complicates the definition and the result is not satisfactory.
Is there any other way to define the moment rotation relationship of a spring ?
Is there anyway to define the momentrotation relationship for beams and columns. I tried placing 2D rotational springs at the connection points of beams and columns with the joint and assigning the hysteretic material but the damage coefficients complicates the definition and the result is not satisfactory.
Is there any other way to define the moment rotation relationship of a spring ?

 Posts: 18
 Joined: Wed Jun 02, 2010 2:05 pm
 Location: Universidad de Chile
Re: defining moment rotation relation for members
Hello,
Defining the momentrotation relationship for beams and columns is possible. Look at this:
http://opensees.berkeley.edu/wiki/index ... Aggregator
Defining the momentrotation relationship for beams and columns is possible. Look at this:
http://opensees.berkeley.edu/wiki/index ... Aggregator
Re: defining moment rotation relation for members
thank you felipe. i will go through it.
Re: defining moment rotation relation for members
I studied the manual and want to ask a question, the relation to be defined in section is MomentCurvature, not MomentRotation, isn't it? (I am trying to add Mz relation to my section)
Re: defining moment rotation relation for members
You can define your spring using either momentrotation of momentcurvature relationship:
If you want to use momentcurvature relationship here is a simple example:
set Mp 103.0474
set EI 71963.55; #sectionsl stiffness
set b 0.01
set matTag 1
set secTag 1
set eleTag 1
uniaxialMaterial Steel02 $matTag $Mp $EI $b 20 0.925 0.15
section Aggregator $secTag $matTag Mz;
element zeroLengthSection $eleTag $nodeR $nodeC $secTag
If you want to use momentrotation here is a simple example:
set phi_y 0.01; # rotation at yielding
set Mp_phi_y [expr Mp/phi_y]
uniaxialMaterial Steel02 $matTag $Mp $Mp_phi_y $b 20 0.925 0.15
element zeroLength $eleTag $nodeR $nodeC mat $matTag dir 6
Make sure to constrain $nodeR and $nodeC usein equalDOF command:
equalDOF $rNodeTag $cNodeTag 1 2
If you want to use momentcurvature relationship here is a simple example:
set Mp 103.0474
set EI 71963.55; #sectionsl stiffness
set b 0.01
set matTag 1
set secTag 1
set eleTag 1
uniaxialMaterial Steel02 $matTag $Mp $EI $b 20 0.925 0.15
section Aggregator $secTag $matTag Mz;
element zeroLengthSection $eleTag $nodeR $nodeC $secTag
If you want to use momentrotation here is a simple example:
set phi_y 0.01; # rotation at yielding
set Mp_phi_y [expr Mp/phi_y]
uniaxialMaterial Steel02 $matTag $Mp $Mp_phi_y $b 20 0.925 0.15
element zeroLength $eleTag $nodeR $nodeC mat $matTag dir 6
Make sure to constrain $nodeR and $nodeC usein equalDOF command:
equalDOF $rNodeTag $cNodeTag 1 2
Re: defining moment rotation relation for members
thank you for the reply and the examples Vesna.
I want to define using Hysteretic material, to be able to control the total rotation mechanism of the beams and columns.
I assign the predefined Hysteretic material to hinge sections of Beamwithhinges element. Does this change the situation since if I define momentrotation (momentcurvature*hinge length) the results semms to be out of order.
I want to define using Hysteretic material, to be able to control the total rotation mechanism of the beams and columns.
I assign the predefined Hysteretic material to hinge sections of Beamwithhinges element. Does this change the situation since if I define momentrotation (momentcurvature*hinge length) the results semms to be out of order.
Re: defining moment rotation relation for members
When defining a section you need to define your material to represent momentcurvature relationship. If you are using zeroLenght element to define rotational spring, then you can define your material to represent momentrotation relationship.
Re: defining moment rotation relation for members
I understand. Thank you very much for your help and also for the fast reply.
Best regards...
Best regards...