Appendix W - High Cycle Fatigue Assesment of Piping Systems

Does anyone have already worked with this Appendix W for fatigue Assesment for high cycle fatigue, as Wave Motion (Inertial Acceleration and Structural Displacement)?

I am working on a FPSO project and for high cycle loads (10E8 cycles), the allowable loads are quite small considering DNV C203 or BS PD 5500 or even API RP 2A fatigue curves.

So, I was reading about these long-term stress range distribution that may be represented by two-parameter Weibull distribution , as per Appendix W and Simplified Fatigue Analysis from DNV C203 Part 5. As far as I undertood, it may be considered for loads that has variable amplitudes during the FPSO lifetime.

Does anyone have any experience with this deterministic fatigue assessment?

Appendix W
http://www.google.com.br/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=4&cad=rja&ved=0CE0QFjAD&url=http%3A%2F%2Ffiles.engineering.com%2Fdownload.aspx%3Ffolder%3D2c8a78fa-86b9-4c06-8f40-d1a86aeb1d3c%26file%3DAPPENDIXW3-25-09.doc&ei=2TLwUPH5CIy89gTB04HYDQ&usg=AFQjCNHVzTYoUnvxBEwYW1OSjURahZ_v4Q&sig2=bWKJXjDD3KSmVzhcGNwCCQ&bvm=bv.1357700187,d.eWU

Marcelo Neves