Dear Wang Please tell me how to compute in detail the Raleigh mass & stiffness Prportioal damping for both concrete and steel? If it is required to define both in concrete & steel bars? Also, if I use implicit dynamic nonlinear time history analysis, it is required to define both parameters.? or use the default values = 0, Please reply me fast. Thanks
HELLO SIR, I WANT TO KNOW WHETHER WE CAN APPLY SEISMIC LOAD IN DISPLACEMENT/ROTATION BOUNDARY CONDITION OR IT SHOULD BE AT ACCELARATION.......PLEASE LET ME KNOW....THANK YOU
Wang do we have to carry out analysis of both step simultaneously to find out natural frequency or first we do frequency analysis and with the help of this data, later we do seismic analysis
hi man, i did same thing but different earthquake acceleration but my displacement values are extremely different but i follow same way and apply same boundry conditions. did you do the same analyse? could you please keep in touch with me.
You are right, it is better practice to consider self weight as an external force in the model, however, it doesn't affect much for linear elastic model. Note that the Mass matrix is constructed according to the weight distribution of the model which means the dynamic effect is correctly considered in this linear elastic model. Since it is a linear elastic model, stress is not that important like displacement. However, the displacement at the Z direction is not correct because I didn't incorporate self weight as body force into the external force vector.
@@fangbowang7317 sir you are using Rayleigh equation a=alpha,b=beta €=1/(2w1)a + w1/2 x b €=.05 w1 take 2.781 w2 take 17.085 And make two equation of w1 and w2 using Rayleigh theory and solve alpha, beta But buy solving them answer is alpha=.23 , Beta= 5.03x10^-3 but you put alpha = 1.508 and beta = .000801 Why??
It's pretty simple to model column and slab as beam and shell elements. I guess you are asking how to connect these two type of elements together. You can go to imechanica.org/files/l7-connections.pdf . I think you can try tie constraint or kinematic coupling constraint.
This is an excellent demonstration of simple case study.
Many thanks.
It could have been easier for a beginner like me if the size of cursor was bigger.
Dear Wang
Please tell me how to compute in detail the Raleigh mass & stiffness Prportioal damping for both concrete and steel? If it is required to define both in concrete & steel bars?
Also, if I use implicit dynamic nonlinear time history analysis, it is required to define both parameters.? or use the default values = 0, Please reply me fast. Thanks
great video man. How will i deal with ground motion in all three directions
Dear Sir
Thanks for your video. Could you please tell us what earthquake you have used in this video?
HELLO SIR,
I WANT TO KNOW WHETHER WE CAN APPLY SEISMIC LOAD IN DISPLACEMENT/ROTATION BOUNDARY CONDITION OR IT SHOULD BE AT ACCELARATION.......PLEASE LET ME KNOW....THANK YOU
Respected sir,
How to apply simultenous horizontal plus vertical ground motion time history earthquake load case in Abaqus?
Sir, How to apply PEER ground motion data for time history analysis in ABAQUS??
Reply plzz
Dear Sir,
I am a beginner in abaqus. Could you please explain how to model lumped masses in columns for both frequency analysis and seismic analysis
Wang do we have to carry out analysis of both step simultaneously to find out natural frequency or first we do frequency analysis and with the help of this data, later we do seismic analysis
hi man, i did same thing but different earthquake acceleration but my displacement values are extremely different but i follow same way and apply same boundry conditions. did you do the same analyse? could you please keep in touch with me.
sir why you put the data of earthquake in displacement boundary why not in acceleration
Hi, do you have any video of geomechanics in abaqus???
jennire vivas geomechanics?just heard by now...is it the mechanism of geometry?
Dear Wang, why do you not considered self weight (gravity load) in the seismic analysis step?
You are right, it is better practice to consider self weight as an external force in the model, however, it doesn't affect much for linear elastic model. Note that the Mass matrix is constructed according to the weight distribution of the model which means the dynamic effect is correctly considered in this linear elastic model. Since it is a linear elastic model, stress is not that important like displacement. However, the displacement at the Z direction is not correct because I didn't incorporate self weight as body force into the external force vector.
Thanks for explanation; your SSI video is great which made my life lot-more easy.
hello, do you know why we put 1 into x direction while defining boundry condition for seismic analayse?
how to add the amplitude if i have the acceleration data only
Dear Sir
how did you find the value of damping coefficients alpha and beta (at 20:39)
check any finite element book to calculate the Rayleigh damping coefficient.
@@fangbowang7317 sir you are using Rayleigh equation a=alpha,b=beta
€=1/(2w1)a + w1/2 x b
€=.05
w1 take 2.781
w2 take 17.085
And make two equation of w1 and w2 using Rayleigh theory and solve alpha, beta
But buy solving them answer is
alpha=.23 , Beta= 5.03x10^-3 but you put alpha = 1.508 and
beta = .000801
Why??
Dear Wang
Please we need to show how to model reinforced concrete column and slab as beam and shell elements and the connection between them. thanks
It's pretty simple to model column and slab as beam and shell elements. I guess you are asking how to connect these two type of elements together. You can go to imechanica.org/files/l7-connections.pdf . I think you can try tie constraint or kinematic coupling constraint.
how can we do seismic analysis in dam
Dear
Can you show me how modaling reinforcement slab concrete with opening ....please
sorry, I have never done this. It takes sometime to figure out.