CSI ETABS - 10 - Torsion Irregularity check | Part 2
ฝัง
- เผยแพร่เมื่อ 30 ก.ย. 2024
- In this lecture, Torsion Irregularity Check as per ASCE Part 2, example 2, is discussed.
1- Torsion Irregularity check excel sheet/spreadsheet
Download: civilmdc.com/2...
2- ASCE 7-16 Minimum Design Loads and Associated Criteria for Buildings and Other Structures
Download: civilmdc.com/2...
EXPLANATION:
a) Torsional Irregularity: Torsional irregularity is defined to exist where the maximum story drift, computed including accidental torsion with Ax =1.0, at one end of the structure transverse to an axis is more than 1.2 times the average of the story drifts at the two ends of the structure. Torsional irregularity requirements in the reference sections apply only to structures in which the diaphragms are rigid or semi-rigid.
b) Extreme Torsional Irregularity: Extreme torsional irregularity is defined to exist where the maximum story drift, computed including accidental torsion with Ax =1.0, at one end of the structure transverse to an axis is more than 1.4 times the average of the story drifts at the two ends of the structure. Extreme torsional irregularity requirements in the reference sections apply only to structures in which the diaphragms are rigid or semirigid.
To compute Torsional Irregularity and Extreme Torsional Irregularity, as specified in ASCE 7-16 Table 12.3-1, item 1a and 1b must be performed and shown in this video.
Structures assigned to Seismic Design Category C, D, E, or F,
where Type 1a or 1b torsional irregularity exists as defined in
Table 12.3-1 shall have the effects accounted for by multiplying
M at each level by a torsional amplification factor (Ax)
The torsional amplification factor (Ax) shall not be less than 1 and
is not required to exceed 3.0. The more severe loading for each
element shall be considered for design.
As per ASCE 7 - 16 Code
********************************************************************
To Build a relationship, Please CLICK THE SUBSCRIBE BUTTON..
1-Download ETABS Software Latest Version
civilmdc.com/c...
2-PASSWORD
www.civilmdc.com
If you face any difficulty...... Please Feel free to contact.
Contact Details
www.civilmdc.com
Professional Trainers
Email ID: civilmdcgroup@gmail.com
#Torsion #Irregularity #TorsionIrregularityCheck
![CSI ETABS - 11 - Modal Analysis Case [ Eigen or Ritz Vectors ] for Fundamental time period/frequency](http://i.ytimg.com/vi/ZcIWWAoGt40/mqdefault.jpg)
![CSI ETABS - 11 - Modal Analysis Case [ Eigen or Ritz Vectors ] for Fundamental time period/frequency](/img/tr.png)
![ผัวเถื่อน - ยูริ โตเกียวมิวสิค [ OFFICIAL MUSIC VIDEO ]](http://i.ytimg.com/vi/P08ORRVDGl8/mqdefault.jpg)
To make a Connection / RELATIONSHIP, Don't forget to press the subscribe button with bell icon to get the latest notifications. My channel :)
th-cam.com/channels/w9kSuR1bTFBmaMEyD_DXvQ.html
Dear M Hussain,
thank you for your valuable videos, Can you make a video on Base Shear and Overturning moment checks? supported by excel sheets based on ASCE7-16..
Regards,
Hy, I changed the eccentricity of the building after the analysis showed irregularity in torsional check. But still the results are the same, do I keep increasing/modifying the value of eccentricity for the building in the load pattern dialogue till the analysis says that the structure is regular ?
Same query.. please answer if u already got the solution.
Dear,
Thanks for the valuable video, Can you send me the Excel sheet because I can not download it correctly.
Please download with desktop... If you still face the issue... You can change browser... Like opera Firefox etc...
Download link is given on the description of the video
Hy, I changed the eccentricity of the building after the analysis showed irregularity in torsional check. But still the results are the same, do I keep increasing/modifying the value of eccentricity for the building in the load pattern dialogue till the analysis says that the structure is regular ? pl reply sir.
How much is irregularity? Share me value
@@sairaiqbal7647 1.22 To 1.88
bro u are doing great job... God bless u
Thanks
i think you should multiply with Lx for Qy and Ly for Qy
Great work for Structural Engineers......Thank you very much God bless you...!
Total eccentricity = e ± Ax*0.05*L
Where L is the dimension of the structure perpendicular to the direction of the applied force? Is it correct?
Yes
Perpendicular to load
@@civilmdc Please refer to UBC 97 Clause 1630.6
Where diaphragms are not flexible, the mass at each level shall
be assumed to be displaced from the calculated center of mass in
each direction a distance equal to 5 percent of the building dimension at that level perpendicular to the direction of the force under
consideration. The effect of this displacement on the story shear
distribution shall be considered
@@cocoymagadia Dear you are right...
On first look... i did not put attention on your question...
now i am editing my answer....
Because in same direction of force, if eccentricity present.... then it will have an effect of eccentricity.
If the building is 'L' shaped then what is the width of the building to be considered in X and Y direction.
In the computation of the eccentricity absolute length... For Ex, should we not use the building dimension Dy not Dx... Same case with Ey, we should be using Dx as the building dimension... Kindly clarify and make the necessary adjustments, so that the group will be guided accordingly. Thnx
You are right
Very useful knowledge given by you thanks sir.
Thanks
What is the code used in the design of this course?
ASCE 7
Why you used UBC 97 but in calculation you used Asce 7-16?
Dear Structural torsional Irregularity is same in both codes.
@@civilmdc thank you. More powers to your channel.
@@engrgep thanks dear.... For Appreciative feedback
thanks a lot it was useful
Welcome
It's not max drift ratio in IS code,, it's middle and avrg ratio not more 1.2, can any please clearify as per IS CODE
It is as per ASCE 7-16
sir my model have torsional irregularity after checking the irregularity I modified the eccentricity in x direction than I analysis the structure again ,after the analysis I get the same irregularity
what do I do next sir
👍🏻
Dear Mr. Engineer. i think you might be mistaken in calculation of Ax because you have to use the MAx and Avg displacements to calculate it not the drift as you did
Dear excel sheet is attached in the description... You can check with ASCE Code..
What is DX?
Done subscribing
Thanks
JAZAKALLAH
Good and clear!
Sire … Is this building designed according to ACI code?
Yes, this course is as per ACI
Here is the full course link on CSI ETABS
th-cam.com/play/PL0h14oMuZXQ5PXbux0l80ox-8gPwcBl5c.html
@@civilmdc thanks. How many Excel sheet this Includes ?
@@mohamedag8366 if any excel sheet discuss in the lecture...then it's download link is given in the description of the video
@@civilmdc if I want to check P-Delta for shear wall , Am I following the same steps for columns like in your video?