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Dear Vesna, I forgot to tell you that, although the recorder for forces gave all zeros, I observe that there are values for deformations (as high as 50 mm), and if I am right, I can use these values to find forces by multiplying deformation with stiffness, can't I? Also, when I record deformations, ...

Dear Vesna, This is a 3-D model of an entire bridge. I have gravity load and the Kobe earthquake load applied bidirectionally (longitudinal and transverse) at the base. I believe that the loads in the longitudinal direction are large enough to record something. Anything else I did not do? Please hel...

Dear Vesna, I need a little advice on recording forces for zeroLength element with ElasticPPGap material. I am assuming a finger joint type of expansion joint, and have used these element and material to model internal expansion joint to observe forces, which would be transmitted in these directions...

Dear oleviuqserh,

I should thank you for clearing things up for me. Thanks again for the references, I will try to search and read them soon.

Regards,
zsherliza

I was using the dynamic analysis to get the eigenvectors (from ''eigen" recorder) to input as my lateral load profile in pushover analysis. I read from the message board that the base shear is the sum of horizontal reactions (transverse or longitudinal) at the base, and this is why I have assum...

Dear oleviuqserh (sorry if this not your name), Thank you very much for your answer. My thesis is on evaluation of a seismic coefficient value for low seismicity countries. As the title may suggest, I am not using any developed response spectrum to conduct pushover analysis. What I have done is get ...

Dear Vesna, I have conducted pushover analysis to plot capacity curve (base shear-displacement) of a MDOF bridge. I applied lateral loads to lumped masses at the deck and pier. There are 27 piers in the bridge structure and I have input lateral loads to all the lumped masses. My lateral load profile...

Dear Vesna, I am trying to simulate a collapse in my 3D bridge structure (I hope this is possible). I have read the example by Laura Eads and adopted her example into my work, however, when I try to run my script it says "can't read sec_p1" no such variable. For your information, I have se...

Hi again,

Has anybody experienced the same problem? I have rechecked my model and just couldn't find explanation of the behavior.

Thanks.

Hi Vesna, Is it possible for a bridge to move only in the transverse directions, no matter in whatever mode i.e. I have displayed mode shapes of the first 8 modes, and they only move in the transverse directions. For your information, I applied gravity load, and 2 earthquake loadings simultaneously ...

Vesna, Thanks for the reply. For your information, I have done all the necessary transformation for elements as you have pointed out here, and I have used the excitation pattern correctly as in the examples (as you have written here as well). I am just wondering about the excitation at the column ba...

Dear Vesna, We all know that ground motions are applied to all nodes using the same record. Since my bridge is curved, some elements are oriented at different angles. I understand why I don't have to worry about element transformation for elements in curved portion, but what about assignment of inpu...

Dear Vesna,

Thank you for the reply. I got the point now.

Dear Ves, Thank you for the answers. I understand that modeshapes are function of mass and stiffness. This is why I think if section dimensions are different, and if I subject EW component longitudinally, I would expect the period and mode shape would be different, and vice versa if I subject it in ...

Hi, I have a few questions: I have a bridge model, my column section is 1500 x 3500 mm (in local y and z axes). I have followed the script for obtaining eigenvectors and period. I applied horizontal components of ground motions simultaneously and run the analysis. Thankfully, the analysis run succes...