i have one doubt tho.. for such a frame structure as u are considering, the stiffness value of 1 storey should be 24EI/L^3 (Two columns) or 48EI/L^3 (Four Columns)???? hope to hear from you soon. Would really like your help on this...
Well I can answer for that question. I can tell that stiffness of the column in this example is 12EI/L^3. However, because each floor has 2 columns you have to multiple by number of columns and it becomes 24EI/L^3. If you have 4 columns then then it will be 4x12EI/L^3. I hope it helps.
@@dachikhutsi2793 well see the thing is when i determined the natural frequency practically or experimentally watevr u call it, i got answer as 25 rad/s.... now i want to verify this value by solving it theoretically by means of equation of motion as shown in video... I have prepared the equation, all i have to do is enter the values... I tried 4 column concept i got ans as 41.4 rad/s.. but when i considered 2 columns i got ans as 27 rad/s which is really close to the one i got practically... So the question arises that while solving theoretically we always consider 2 columns for such frame cases?? Is it a thing that while solving eq of motion, one hasbto consider 2D figure instead of 3D figure??Btw thanks for the reply 👍👍
Hi, I don't think your matrices are correct. Orthogonally you matrices should be 2, 2, 1 because one end is fixed and another end is free, thus you should have k1+k2, k2+k3, k3
Sir how can be solve 6× 6 matrix. Of stiffness and mass matrix in excel for mode shape
i have one doubt tho.. for such a frame structure as u are considering, the stiffness value of 1 storey should be 24EI/L^3 (Two columns) or 48EI/L^3 (Four Columns)???? hope to hear from you soon. Would really like your help on this...
Well I can answer for that question. I can tell that stiffness of the column in this example is 12EI/L^3. However, because each floor has 2 columns you have to multiple by number of columns and it becomes 24EI/L^3. If you have 4 columns then then it will be 4x12EI/L^3. I hope it helps.
@@dachikhutsi2793 well see the thing is when i determined the natural frequency practically or experimentally watevr u call it, i got answer as 25 rad/s.... now i want to verify this value by solving it theoretically by means of equation of motion as shown in video... I have prepared the equation, all i have to do is enter the values... I tried 4 column concept i got ans as 41.4 rad/s.. but when i considered 2 columns i got ans as 27 rad/s which is really close to the one i got practically... So the question arises that while solving theoretically we always consider 2 columns for such frame cases?? Is it a thing that while solving eq of motion, one hasbto consider 2D figure instead of 3D figure??Btw thanks for the reply 👍👍
@@kevinwadia3325 do you use what's app or anything? I would love to help and I know the answer to your question but I need to explain it to you
@@kevinwadia3325 you probably have pinned support connection where you have to use k= 3EI/L^3
@@dachikhutsi2793 sry i dosed off... It was 3:30AM so 😂😂.... Well its a simple CPVC physical model and all of the joints are fixed...
Hi, I don't think your matrices are correct. Orthogonally you matrices should be 2, 2, 1 because one end is fixed and another end is free, thus you should have k1+k2, k2+k3, k3
He has rectified that in his next video where he solves the same case by Mathcab
How do i define de matrix k?