Seismic Resisting Elements

[joelperez]

Hi, the local building code from where I live states that every element that its part of the seismic force resisting system has to
come from the foundations hence you can't have a seismic resisting element that begin in the 2nd floor slab. I was wondering if you guys know what does the ASCE 7-16 says about this?

 

[r13]

Hi, the local building code from where I live states that every element that its part of the seismic force resisting system has to come from the foundations...

I'll change the words in bold to "be able to deliver the seismic forces down to" instead. Please post the exact text/provision in your code.

 

[HTURKAK]

Let me change your statement : The SFRS shall have continuous load resistance path with adequate redundancy such that the structure can ride over local damage .

This statement is copy and paste from ASCE 7 ( 12.1.3 Continuous Load Path and Interconnection. A continuous load path, or paths, with adequate strength and stiffness shall be provided to transfer all forces from the point of application to the final point of resistance.....)

You can see the ASCE 7 classification and limitations for SFRS at Table 12.2-1 .

The requirement for dual system is , the secondary moment frame shall be CAPABLE OF RESISTING AT LEAST 25% of prescribed seismic forces..

Regarding your statement ' you can't have a seismic resisting element that begin in the 2nd floor slab ' I understand the use of floating column which springs from a beam ...and should be avoided..If unavoidable, it should be interconnected and detailed properly to transfer lateral loads and shall have drift performance similar to SFRS.

If you post the exact provision in your local code, you may get better responds..