ASCE 7-05 Increasing Factors (overstrength, redundancy)
ASCE 7-05 Increasing Factors (overstrength, redundancy)
(OP)
I have been going through the ASCE 7-05 as I am starting to get into higher seismic areas. I think I have a grasp as to when the redundancy factor would be greater than 1.0 however I am somewhat confused as to when the overstrangth factor comes into play. I know that you would apply the overstrength factor to say a collector or that you would apply a 1.4 increase for elements of the wall anchorage system per 12.11.2.2.2, however Im unsure as to when else I would apply the overstrength factor that is given in table 12.2-1. Can anyone shine some light on the issue or any other increasing factor that I have not mentioned.






RE: ASCE 7-05 Increasing Factors (overstrength, redundancy)
RE: ASCE 7-05 Increasing Factors (overstrength, redundancy)
The code usually states that the overstrength factor would be applied only where it is specifically required.
RE: ASCE 7-05 Increasing Factors (overstrength, redundancy)
I didnt see anywhere that the overstength factor would apply to the diaphragm. When you say diaphragm are you referring to the attachment of the diaphragm to the steel supports?
RE: ASCE 7-05 Increasing Factors (overstrength, redundancy)
RE: ASCE 7-05 Increasing Factors (overstrength, redundancy)
I've attached a memo that we used on another project and it is for a specific situation - but the logic flow might help you see why diaphragms could be considered as part of the seismic force resisting system: