Link Element (Takeda) use for Hysteretic Behavior
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- Posts: 42
- Joined: 29 Apr 2014, 15:42
Link Element (Takeda) use for Hysteretic Behavior
I'm analysing USCS Full-Scale Blind Prediction Contest Bridge Pier
under Dynamic Time History Analysis. For Capturing its stiffness
degradation behavior, I've added Takeda link element at the bottom.
I've calibrated the link element by performing static pushover
Analysis and converting the Capacity Curve to a bilinear curve.
The static pushover Analysis model can be seen here
https://drive.google.com/folderview?id= ... sp=sharing
Fy for the link =600.17 kN , other calibrating parameters can be
seen in the model.
I'm not getting any force in the Link Element (though yielding
seems to be taking place from performance Criteria Check)
Please check my model. Direction of interest for analysis is X-axis.
https://drive.google.com/folderview?id= ... sp=sharing
(I'm confused regarding which node to restrain. Both the coincident structural nodes or only one and which one ? Also which node to apply the time history ? Also does it make any difference if i change the order of first two initially coincident nodes of the link element?)
under Dynamic Time History Analysis. For Capturing its stiffness
degradation behavior, I've added Takeda link element at the bottom.
I've calibrated the link element by performing static pushover
Analysis and converting the Capacity Curve to a bilinear curve.
The static pushover Analysis model can be seen here
https://drive.google.com/folderview?id= ... sp=sharing
Fy for the link =600.17 kN , other calibrating parameters can be
seen in the model.
I'm not getting any force in the Link Element (though yielding
seems to be taking place from performance Criteria Check)
Please check my model. Direction of interest for analysis is X-axis.
https://drive.google.com/folderview?id= ... sp=sharing
(I'm confused regarding which node to restrain. Both the coincident structural nodes or only one and which one ? Also which node to apply the time history ? Also does it make any difference if i change the order of first two initially coincident nodes of the link element?)
Re: Link Element (Takeda) use for Hysteretic Behavior
Dear adeelfaisal,
You should restrain just the one of the nodes and apply the loads to the restrained one. The second node of the link element(without any restraints) will be the first node of the column element. The only difference in changing the order of the initially coincident nodes of the link element lies in the link's local axes.
You should restrain just the one of the nodes and apply the loads to the restrained one. The second node of the link element(without any restraints) will be the first node of the column element. The only difference in changing the order of the initially coincident nodes of the link element lies in the link's local axes.
Zoi Gronti
Seismosoft Srl.
Seismosoft Srl.
Re: Link Element (Takeda) use for Hysteretic Behavior
Hi adeelfaisal. As z.gronti points out, the second node of the link element needs to be the first node of the column element. In your model in question, this may be accomplished by simply changing the first node for the column from '1' to '1bis'. There are other ways to get the same effect, but this is the most straightforward.
As modeled, the first node of your column was restrained and the link was simply along for the ride with no response. The above-mentioned change will capture the link behavior you seek. I encourage you to sketch out your model and try to understand why this is true.
Best of luck adeelfaisal.
As modeled, the first node of your column was restrained and the link was simply along for the ride with no response. The above-mentioned change will capture the link behavior you seek. I encourage you to sketch out your model and try to understand why this is true.
Best of luck adeelfaisal.
Tim Huff
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- Joined: 29 Apr 2014, 15:42
Re: Link Element (Takeda) use for Hysteretic Behavior
Thank you very much Z.Gronti for your response. This has solved my problem.
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Re: Link Element (Takeda) use for Hysteretic Behavior
Thank you Huffte. I appreciate your suggestion. I changed the first node of my column to 1_bis and as you had said, i got the behavior i was seeking. Thanks again Huffte.
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- Joined: 03 Dec 2011, 00:10
Re: Link Element (Takeda) use for Hysteretic Behavior
I am analyzing a RC circular concrete column for static time history analysis. For the stiffness degradation I used Takeda Link element for the static time history analysis.
I am getting base shear and displacement, but not getting force in the Link element.
As per the previous discussion on forum, I restrain the first node and unrestained the second node, then not I was not getting any force. After that I restrain the second node, the base shear and displacement is good, but no force in the link element.
Anybody, could please check the mode.
https://docs.google.com/file/d/0B3tbcUu ... pIZDA/edit
https://drive.google.com/open?id=0B3tbc ... authuser=0
Thanks
Anant
I am getting base shear and displacement, but not getting force in the Link element.
As per the previous discussion on forum, I restrain the first node and unrestained the second node, then not I was not getting any force. After that I restrain the second node, the base shear and displacement is good, but no force in the link element.
Anybody, could please check the mode.
https://docs.google.com/file/d/0B3tbcUu ... pIZDA/edit
https://drive.google.com/open?id=0B3tbc ... authuser=0
Thanks
Anant
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- Posts: 42
- Joined: 29 Apr 2014, 15:42
Re: Link Element (Takeda) use for Hysteretic Behavior
Are you applying the load to the restrained end and is the second node of the link the first node of your column? I tried to download your model but access was denied.
quote:Originally posted by anantparghi
I am analyzing a RC circular concrete column for static time history analysis. For the stiffness degradation I used Takeda Link element for the static time history analysis.
I am getting base shear and displacement, but not getting force in the Link element.
As per the previous discussion on forum, I restrain the first node and unrestained the second node, then not I was not getting any force. After that I restrain the second node, the base shear and displacement is good, but no force in the link element.
Anybody, could please check the mode.
https://docs.google.com/file/d/0B3tbcUu ... pIZDA/edit
https://drive.google.com/open?id=0B3tbc ... authuser=0
Thanks
Anant
quote:Originally posted by anantparghi
I am analyzing a RC circular concrete column for static time history analysis. For the stiffness degradation I used Takeda Link element for the static time history analysis.
I am getting base shear and displacement, but not getting force in the Link element.
As per the previous discussion on forum, I restrain the first node and unrestained the second node, then not I was not getting any force. After that I restrain the second node, the base shear and displacement is good, but no force in the link element.
Anybody, could please check the mode.
https://docs.google.com/file/d/0B3tbcUu ... pIZDA/edit
https://drive.google.com/open?id=0B3tbc ... authuser=0
Thanks
Anant
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- Posts: 27
- Joined: 03 Dec 2011, 00:10
Re: Link Element (Takeda) use for Hysteretic Behavior
Hi Adeel,
Thank you very much for your reply. I am running static time history analysis.I restrained the second node of the link which is the first node of column. The first node of the link was restrained only y+rx+rz. The load I applied to the top of the column with axial mass, and lateral cyclic load.
quote:Originally posted by adeelfaisal
Are you applying the load to the restrained end and is the second node of the link the first node of your column? I tried to download your model but access was denied.
quote:Originally posted by anantparghi
I am analyzing a RC circular concrete column for static time history analysis. For the stiffness degradation I used Takeda Link element for the static time history analysis.
I am getting base shear and displacement, but not getting force in the Link element.
As per the previous discussion on forum, I restrain the first node and unrestained the second node, then not I was not getting any force. After that I restrain the second node, the base shear and displacement is good, but no force in the link element.
Anybody, could please check the mode.
https://docs.google.com/file/d/0B3tbcUu ... pIZDA/edit
https://drive.google.com/open?id=0B3tbc ... authuser=0
Thanks
Anant
Thank you very much for your reply. I am running static time history analysis.I restrained the second node of the link which is the first node of column. The first node of the link was restrained only y+rx+rz. The load I applied to the top of the column with axial mass, and lateral cyclic load.
quote:Originally posted by adeelfaisal
Are you applying the load to the restrained end and is the second node of the link the first node of your column? I tried to download your model but access was denied.
quote:Originally posted by anantparghi
I am analyzing a RC circular concrete column for static time history analysis. For the stiffness degradation I used Takeda Link element for the static time history analysis.
I am getting base shear and displacement, but not getting force in the Link element.
As per the previous discussion on forum, I restrain the first node and unrestained the second node, then not I was not getting any force. After that I restrain the second node, the base shear and displacement is good, but no force in the link element.
Anybody, could please check the mode.
https://docs.google.com/file/d/0B3tbcUu ... pIZDA/edit
https://drive.google.com/open?id=0B3tbc ... authuser=0
Thanks
Anant
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- Posts: 42
- Joined: 29 Apr 2014, 15:42
Re: Link Element (Takeda) use for Hysteretic Behavior
Dear Anantparghi
I've checked your model.I'm not very sure about why link is not
behaving in the expected way but i would suggest you to check if
you have correctly calibrated the link element. Fy =500 kN for the
Takeda Link is the default value used by the program. You need to
find out the actual parameters for your column by performing
static pushover analysis for your column to get the capacity curve
for your column and converting the capacity curve to idealized
bilinear curve.
Best of Luck-- Anant
quote:Originally posted by anantparghi
Hi Adeel,
Thank you very much for your reply. I am running static time history analysis.I restrained the second node of the link which is the first node of column. The first node of the link was restrained only y+rx+rz. The load I applied to the top of the column with axial mass, and lateral cyclic load.
quote:Originally posted by adeelfaisal
Are you applying the load to the restrained end and is the second node of the link the first node of your column? I tried to download your model but access was denied.
quote:Originally posted by anantparghi
I am analyzing a RC circular concrete column for static time history analysis. For the stiffness degradation I used Takeda Link element for the static time history analysis.
I am getting base shear and displacement, but not getting force in the Link element.
As per the previous discussion on forum, I restrain the first node and unrestained the second node, then not I was not getting any force. After that I restrain the second node, the base shear and displacement is good, but no force in the link element.
Anybody, could please check the mode.
https://docs.google.com/file/d/0B3tbcUu ... pIZDA/edit
https://drive.google.com/open?id=0B3tbc ... authuser=0
Thanks
Anant
I've checked your model.I'm not very sure about why link is not
behaving in the expected way but i would suggest you to check if
you have correctly calibrated the link element. Fy =500 kN for the
Takeda Link is the default value used by the program. You need to
find out the actual parameters for your column by performing
static pushover analysis for your column to get the capacity curve
for your column and converting the capacity curve to idealized
bilinear curve.
Best of Luck-- Anant
quote:Originally posted by anantparghi
Hi Adeel,
Thank you very much for your reply. I am running static time history analysis.I restrained the second node of the link which is the first node of column. The first node of the link was restrained only y+rx+rz. The load I applied to the top of the column with axial mass, and lateral cyclic load.
quote:Originally posted by adeelfaisal
Are you applying the load to the restrained end and is the second node of the link the first node of your column? I tried to download your model but access was denied.
quote:Originally posted by anantparghi
I am analyzing a RC circular concrete column for static time history analysis. For the stiffness degradation I used Takeda Link element for the static time history analysis.
I am getting base shear and displacement, but not getting force in the Link element.
As per the previous discussion on forum, I restrain the first node and unrestained the second node, then not I was not getting any force. After that I restrain the second node, the base shear and displacement is good, but no force in the link element.
Anybody, could please check the mode.
https://docs.google.com/file/d/0B3tbcUu ... pIZDA/edit
https://drive.google.com/open?id=0B3tbc ... authuser=0
Thanks
Anant
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- Posts: 42
- Joined: 29 Apr 2014, 15:42
Re: Link Element (Takeda) use for Hysteretic Behavior
I've obtained Hysteresis Plot using Takeda Link.
I've to find stiffness degradation resulted from Dynamic Time History
Load. How can i find the stiffness degradation from the hysteresis
plot. I guess that the slope of the final loading branch should be
considered as the degraded stiffness and compared with the initial
stiffness, Sy. Is it the right approach ? Comment plz
Seismostruct model https://drive.google.com/folderview?id= ... sp=sharing
Excel Sheet containing the plot https://drive.google.com/file/d/0B1zFr_ ... sp=sharing
I've to find stiffness degradation resulted from Dynamic Time History
Load. How can i find the stiffness degradation from the hysteresis
plot. I guess that the slope of the final loading branch should be
considered as the degraded stiffness and compared with the initial
stiffness, Sy. Is it the right approach ? Comment plz
Seismostruct model https://drive.google.com/folderview?id= ... sp=sharing
Excel Sheet containing the plot https://drive.google.com/file/d/0B1zFr_ ... sp=sharing