where ∆σi is the stress range corresponding to
which the cycles to failure Ni is calculated.
Further, the monopile structure in this study consists of a weldment of
90mm thickness, therefore a thickness correction is applied according to
the guidelines provided in DNVGL-RP-C203 standard such thattref denotes a thickness of 25mm and t is
the corrected weld thickness. Since the plate thickness and weld width,
both affect the local stress field at the weld toe, the effective
thickness of the plate was given by Eq. 8. For the weld geometry
considered in this study, the values of plate thickness T and
weld width L are 90mm and 54mm, respectively as shown in Fig. 5.