On the modelling of the unstable breaching process

D. Weij

Research output: ThesisDissertation (TU Delft)

60 Downloads (Pure)


Breaching is an important production mechanism for stationary suction dredgers. It is a process occurring in submerged sandy slopes, which mostly occurs in dense sandy soils with a low permeability. The process is initiated by the formation of a slope under water, whose angle is steeper than the internal friction angle, called the breach face. For dredging related breaching, this steep slope is created by a suction dredger, but it can also be formed after initial shear failure, caused by over steepening due to erosion, an earthquake, or an outwardly directed water flow. During breaching process, this steep slope is semi-stable due to negative pore pressure. Instead of a shear failure, particles are released one by one from the breach face, making it seem like the breach face is slowly moving backwards. The released particles form a density current that flows away from the breach face, and can be collected by a stationary suction dredger. When the size of the breach face increases over time, we have an unstable breach.
Original languageEnglish
Awarding Institution
  • Delft University of Technology
  • van Rhee, C., Supervisor
  • Keetels, G.H., Advisor
Award date2 Apr 2020
Publication statusPublished - 2020


  • Dredging
  • numerical modelling
  • turbidity currents
  • breaching

Cite this