Stability of scour protection due to earthquake-induced liquefaction: centrifuge modelling

Daniella E. Escribano, Andrew Brennan

Research output: Contribution to journalArticlepeer-review

2 Citations (Scopus)
276 Downloads (Pure)


A key aspect of permanent offshore structures is protection against scour. This is typically in the form of a blanket of coarse gravel or cobbles surrounding the structure. These coarse particles are selected for their high resistance to being displaced by strong currents and thus protect the underlying finer sand particles from scour. However, in the event of an earthquake, the foundation sand may be susceptible to some degree of liquefaction. This research investigates the effects of seismic-induced liquefaction over a scour blanket, and if sinking is inhibited by some combination of the additional effective stress imposed by the gravel together with the interlocking resistance that develops when coarse particles are subjected to relative displacements. In order to evaluate the stability of scour protection blankets, a programme of physical modelling was carried out, involving the assessment of different configurations of stone layers over a liquefiable material, and a monopiletype foundation. Models were subjected to scaled base shaking equivalent to earthquake loading. A mass-balance of particle sinkage showed that a filter layer was critical for maintaining the integrity of the armour stones. Based on displacement and pore water pressure measurements, it was found that the presence of the scour protection blankets improved the response of the liquefiable sand under seismic loading, and even inhibited the occurrence of liquefaction. This implies that a well-designed scour protection blanket can assist in protecting against earthquake effects also.
Original languageEnglish
Pages (from-to)50-58
Number of pages9
JournalCoastal Engineering
Early online date3 Sept 2017
Publication statusPublished - Nov 2017


  • Scour protection
  • Sand
  • Shaking table
  • Centrifuge modelling
  • Liquefaction
  • Monopile


Dive into the research topics of 'Stability of scour protection due to earthquake-induced liquefaction: centrifuge modelling'. Together they form a unique fingerprint.

Cite this