Irregularity assessment in low seismicity zones (DCL) according to EC8

[Refaatfaraj]

Dear Colleagues
I would like to ask if there is a clear statements or recommendations in (Eurocode 8 ) about ignoring plan and elevation irregularity assessment in low seismicity zones (DCL) .
Note : If possible the response attached with reference .
Any help will be highly appreciated
Best,

 

[Guest262653]

Check section 5.3 - Design to EN1992-1-1.

 

[Refaatfaraj]

Hi avscorreia
Thank you for your response .
As mentioned on clause 5.3.3(1) that regardless of the structure system and the regularity in elevation .
As far as I understand , the regularity verification for bout plan and elevation can be ignored in (DCL) .
So , do you think the later force method of analysis (EN 1998-1:2004E & Clause 4.3.3.2) will be adequate for all cases in DCL ?
Thanks in advance
Best ,

 

[Guest262653]

No. If the structural is irregular, a RSA should be used. Not related to code but to the structural behaviour and analysis method limitations.

 

[Refaatfaraj]

Do you mean that even the conditions to apply the seismic analysis method in table (4.1 & EC8) are applicable even the low seismicity zones (DCL) ?

Note : the table is attached

 

[Guest262653]

Forget the code. What analysis method is adequate to your structure, taking into account its regularity and the analysis methods limitations?

 

[Refaatfaraj]

I applied the Modal Response Spectrum to my structure since I have both irregularity (Plan & Elevation ) .
Knowing that the peak Ground acceleration = 0.05g
Please , take a look to the attached capture .

 

[Guest262653]

If you have already used RSA, there's no need to design using the simplified lateral force method, right?

 

[Refaatfaraj]

So, the conclusion is that the regularity verification for both plan and elevation should be applicable even in low seismicity zones (DCL) .

 

[Guest262653]

The conclusion is that the analysis method should be applicable to your structural system.

 

[Refaatfaraj]

Sure , so the regularity verification for both plan and elevation in low seismicity zones (DC) couldn’t be ignored , aren’t you ?