The USGS spectral response graphs are all based off of 5% damping, however IEEE-693 and ASCE 113 for electrical substation design both state that a maximum damping value of 2% must be assumed for all structures.
Is there any way to convert the USGS 5% damped response spectrum into a 2% damped one?
On a side note, why doesn't the USGS tool allow you to specify damping? From what I've read 5% damping is really only accurate for reinforced concrete and some steel structures, whereas most steel structures should be around the 1%-5% range.
Is there any way to convert the USGS 5% damped response spectrum into a 2% damped one?
On a side note, why doesn't the USGS tool allow you to specify damping? From what I've read 5% damping is really only accurate for reinforced concrete and some steel structures, whereas most steel structures should be around the 1%-5% range.