I'm not sure of your specific question, but in broad terms, the overstrength provisions are included to ensure that plastic hinges in the structure occur where they are supposed to, recognizing that some components (specifically, those that are supposed to hinge or buckle under seismic loading) may be stronger than expected, while components that are supposed to remain elastic, may not be stronger than they are supposed to be.
Rod Smith, P.E., The artist formerly known as HotRod10
Are you asking about ASCE7-16 Table 12.2-1 SFRS Type H: Steel Systems not specifically detailed for seismic resistance?
Pretty much need to follow through the detailing requirements, Overstrength Factor might be applied to steel components of the system, it might be applied to concrete components of the system. Need to follow detailing requirements as indicated in the table I mentioned above to find where it might apply.
To clarify, ASCE 7 in table 12.2-1 has a H. STEEL SYSTEMS NOT SPECIFICALLY DETAILED FOR SEISMIC RESISTANCE with an Overstrength of 3.0 value. But the AISC 341 doesn't have specifications or requirements for that system. So the overstrength factor has no utility for designing that system.
It might apply to the anchorage calculations per ACI, it might also apply if there are any irregularities. Collector design, perhaps diaphragm design. Just because it isn't called out in 341 doesn't mean you wont need to use it elsewhere in the system.
Thanks for your answers.
I think you accept overstrength factor will NOT be usable for the calculations and design for the main members of the Lateral force resisting system and their connections.
Well overstrength can be useful if you have want to protect the yielding element of your system. Since your using that system your left on your own to detail it to get ductility to match the R factor you have selected. I haven't really investigated this in detail so I am not going to accept your statement that you say I accept, but I will again refer to my first post where you need to review detailing requirements, and I will add that you want to ensure your system doesn't have a brittle failure. It is a good idea to identify the yielding components of your system and you could use overstrength on the other components to ensure good seismic performance.
Even in structures not detailed for seismic, elements that could cause the building to fail in a brittle fashion like connections, collectors, etc. should be designed with the over strength factor although in many cases, it doesn't matter. The R value is a divider that allows you to design your building for less loading based on how much energy will be dissipated by the structure itself.
In very simple terms, consider a building with a total calculated seismic load of 60 kips. If you have an R value of 3, you divide the actual predicted load by 3 to get 20 kips. Then when you apply the over strength factor of 3 to connections and collectors, you multiply that loading back up to 60 kips. So in a building that's not detailed for seismic, you're designing the parts that would fail in a brittle fashion for the full seismic loading. (Do not kill me on the super simple, dumbed down example. I understand that you don't design a building for 60 kips, you design individual components. Please don't miss the forest for the trees.)
In light buildings that would qualify for "not detailed for seismic", that full seismic load is usually lower than wind loading so using the over strength factor doesn't impact your building.
But heavy structures that qualify for "not detailed for seismic" could still have the seismic control, at least at the brittle elements. This is where you have to be careful with "not detailed for seismic." It doesn't say "not designed for seismic."
