ASCE 7 : Provision for SDC - B

[McGill10]

Use of Amplified load combination in SDC -B.
I could not find any section on ASCE 7 that requires the use of amplified load combination(includes omega factor).Could anyone confirm whethere it applies or not for SDC-B. It says SDC C and above per section 12.10.2.1 for collector elements. My thought is there should be situations where it requires otherwise why there is a omega factor for SDC- B sturctural systems.
Would really appreciate your experience and practice.
Regards,
Mcgill

 

[phamENG]

Check out this article, number 6. It gives a good list of the places in chapter 12 that require use of over strength regardless of SDC.

 

[McGill10]

Thanks,Nice Article.That answers a lot of questions about seismic design code.

 

[HTURKAK]

This exemption is for only design of collector elements for SDC -B.

Lets have a look to the 12.10.2.1;

( 12.10.2.1 Collector Elements Requiring Load Combinations Including Overstrength for Seismic Design Categories C through F. In structures assigned to Seismic Design Category C, D, E, or F, collector elements (Fig. 12.10-1) and their...)
That is ,the collector elements could be designed with using load combination not including omega factor..

Other requirements


12.2.5.2 Cantilever Column Systems. ....Foundation and other elements used to provide overturning
resistance at the base of cantilever column elements shall be designed to resist the seismic load effects, including overstrength
of Section 12.4.3.


12.3.3.3 Elements Supporting Discontinuous Walls or Frames. Structural elements supporting discontinuous walls
or frames of structures that have horizontal irregularity Type 4 of Table 12.3-1 or vertical irregularity Type 4 of Table 12.3-2
shall be designed to resist the seismic load effects, including overstrength of Section 12.4.3.

Regarding the other cases , look to ACI and AISC ..