An Analytical Method for Jack-Up Riser’s Fatigue Life Estimation

Abstract EN

In order to determine whether a special sea area and its sea state are available for the jack-up riser with surface blowout preventers, an analytical method is presented to estimate the jack-up riser’s wave loading fatigue life in this study.

In addition, an approximate formula is derived to compute the random wave force spectrum of the small-scale structures.

The results show that the response of jack-up riser is a narrow band random vibration.

The infinite water depth dispersion relation between wavenumber and wave frequency can be used to calculate the wave force spectrum of small-scale structures.

The riser’s response mainly consists of the additional displacement response.

The fatigue life obtained by the formula proposed by Steinberg is less than that of the Bendat method.