WP 4 – Advanced derivation of cyclic soil design parameters

Particular focus is on the effect of cyclic loading conditions. NGI has developed in the last four decades a robust and validated procedure, which was applied in both oil and gas projects as well as offshore wind projects. This procedure has been continuously improved in internally funded research projects and is currently revisited in frame of the ongoing RCN KPN project WAS-XL. The work conducted in WAS-XL is to develop an application oriented methodology for more efficient evaluation of the effect of cyclic loading for ULS, SLS and FLS, under the particular conditions of OWTs.

The goal of WP4 is to develop a module for assessing cyclic soil design profiles, which can be applied to a wide range of foundation concepts, soil types and general boundary conditions. Particular attention requires the identification of the dominating failure mechanism, which depends on the soil profile, drainage conditions, and foundation geometry. Further, the framework for cyclic accumulation, which was developed primarily for ULS analyses, shall be extended to LS analyses, where the soil is not at critical failure. It is expected that the results from WAS-XL will provide a theoretical basis for this task.