Dear engineers,
My concern is about Sustained stress index of 0.75*SIF & 1.0*SIF. For the articles, books and even codes I've read, I did not found any concrete basis when to use these two options. I know that these two options was stated as per (#1-34 (2/23/81)) and (#6-03 (12/14/87)) but this seems confusing.Based on mechanical engineering news-jan 01. It was stated "So for the time being I would recommend that this factor of 0.75SIF>= 1.0=SSI be used in analysis" and "0.75SIF as a multiplier is probably not 100% right but it is more approriate than 1.0".

My question is, What specific condition to use 0.75 or 1.0 as Sustained SIF Multiplier?

Please share your Idea..!

Any responce subject to this matter is highly appreciated!


Regards,
Nald