Scale factor value in x direction is double in scale y direction and if mass participation period scale is more first mode what is the problem. Please suggest me
Hello sir, Im using SAP2000 for structural analysis. In response spectrum case, stress values on shell elements are seen as 0. When I define static seismic case with the values that produces same base shear, static case gives stress on shell elements but response spectrum case still not. How can I fix that? Is there any suggestion? Thanks in advance.
Dynamic analysis has many uncertainties. To ensure safety if the base shear is less than the base shear from the equivalent static load method, we have to scale it up.
Hello! Im currently studying civil engineering. Should i rescale the scale factor if the response spectrum base shear turns out to be higher? Any insights on when we should or should not?
According to IS 1893-2016 part-1, If the design base shear from the equivalent static method is coming out to be less than the base shear from dynamic analysis, the scaling should be done as given in the code.
The response spectrum given in the IS1893 code is elastic. By using this scale factor we consider the Response reduction factor R which considers the ductility in the building. We also consider I in the scale factor. You can refer to the CSI America website for further reference.
@@CivilSAC now its not needed in updated version of etabs for 1st time analysis factor should be (g) I have checked with manual calculation. In website that wiki page that was uploaded in 2012 and for old versions
@@nraj2597 Are you sure sir? I am also getting some huge scale factors like 30-35 when I am doing large building designs. even I noticed that CSI website was giving the answer for old versions. So Initially should I take a scale factor of 9.8 in my analysis??Pls help.
Short and simple...so helpful
Thanks.
short and simple.. nice brother liked it♥️✔🎉🎊
Hello, just had a look at the CSI website and it seems that the scale factor is equal to Ig/R. Is there a reason why you divided by 2?
Ig/2R is used for IS 1893 code however Ig/R is used with ASCE 7.
I hope this clears things up.
Scale factor value in x direction is double in scale y direction and if mass participation period scale is more first mode what is the problem. Please suggest me
Hello sir, Im using SAP2000 for structural analysis. In response spectrum case, stress values on shell elements are seen as 0. When I define static seismic case with the values that produces same base shear, static case gives stress on shell elements but response spectrum case still not. How can I fix that? Is there any suggestion?
Thanks in advance.
Hello sir..
I would like to know about the source/code book from where formula for scale factor. Ig/2R is used.
You refer to the CSI website.
what is the meaning of scaling upto base shear due to EQ? what happens when we dont scale up?
Dynamic analysis has many uncertainties. To ensure safety if the base shear is less than the base shear from the equivalent static load method, we have to scale it up.
@@CivilSAC thank u sir subscribed ur channel
Whats next step? After doing scalefactor
Hello! Im currently studying civil engineering. Should i rescale the scale factor if the response spectrum base shear turns out to be higher? Any insights on when we should or should not?
According to IS 1893-2016 part-1, If the design base shear from the equivalent static method is coming out to be less than the base shear from dynamic analysis, the scaling should be done as given in the code.
Scale factor will be same or differ for Time history
The scale factor will be different for different time histories.
How to calculate scale factor for time history data
Please refer to this video on my channel
th-cam.com/video/XAQt9OB2KWc/w-d-xo.html
Initially we are taking scale factor as If/2R why??? Please tell the reason and reference..I Am taking it as 1 in spectrum case..plz help..
The response spectrum given in the IS1893 code is elastic. By using this scale factor we consider the Response reduction factor R which considers the ductility in the building. We also consider I in the scale factor. You can refer to the CSI America website for further reference.
@@CivilSAC now its not needed in updated version of etabs for 1st time analysis factor should be (g)
I have checked with manual calculation.
In website that wiki page that was uploaded in 2012 and for old versions
@@nraj2597 Are you sure sir? I am also getting some huge scale factors like 30-35 when I am doing large building designs. even I noticed that CSI website was giving the answer for old versions. So Initially should I take a scale factor of 9.8 in my analysis??Pls help.
What is for if V2 is>V1
No, need to scale.
Here scale factor must be 9.81
If your unit of acceleration is m/s2, then you can use 9.81.