New Design Approach for Large Diameter Offshore Monopiles Based on Physical and Numerical Modelling

Monopiles with diameters of more than 4 m are suitable foundations for offshore wind farms in water depths of about 30 m. They are subjected to high numbers of cyclic horizontal loads due to wind and water waves. The paper presents a new practical design concept for cyclic horizontally loaded monopile foundations in water saturated sands and considering pile displacement and pore pressure accumulation effects. The design approach is based on physical and numerical modelling. In the design concept, the pile displacements due to cyclic horizontal loads are predicted by means of an Extended-Strain-Wedge-Model (ESWM) approach. The extension of the known SWM (Norris, 1986) mainly concerns a more realistic representation of the cyclic soil-monopile behaviour in water saturated sands. A possible pore water pressure accumulation around the pile is evaluated on the basis of the three-dimensional fully coupled two-phase finite element analysis. The design approach has been validated using the results from the physical 1g pile model tests.

Language

  • English

Media Info

  • Media Type: Web
  • Pagination: pp 356-365
  • Monograph Title: GeoCongress 2012: State of the Art and Practice in Geotechnical Engineering

Subject/Index Terms

Filing Info

  • Accession Number: 01530376
  • Record Type: Publication
  • ISBN: 9780784412121
  • Files: TRIS, ASCE
  • Created Date: Nov 12 2013 2:02PM