Mechanics and response of a surface rock block subjected to pressure fluctuations: A plucking model and its application

Yii Wen Pan*, Kuo Wei Li, Jyh Jong Liao

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

6 Scopus citations

Abstract

Plucking (removal of rock blocks) is often the dominant mechanism for producing a scour hole on riverbeds comprised of heavily jointed rock masses being subjected to pressure fluctuations from a jet flow. This paper explores the mechanics and response of a surface block subjected to pressure fluctuations. First a particle-flow simulation was conducted to demonstrate how repeated pressure fluctuations are able to gradually remove rock bridges in discontinuities surrounding a rock block, if a pressure fluctuation's intensity is substantial. As a consequence, these weak planes may become fully persistent. The block's uplift speed then depends on the pressure differences on the opposite (horizontal) faces, and the frictional resistance of the lateral discontinuities. This paper proposes a theoretical framework to model the mechanics and response of a rock block subjected to a sinusoidal pressure fluctuation. This model can be applied to estimate the development of a scour hole, through plucking, during a specific flood event. An example demonstrates the applicability of the proposed approach in predicting the potential depth of the scour hole.

Original languageEnglish
Pages (from-to)1-10
Number of pages10
JournalEngineering Geology
Volume171
DOIs
StatePublished - 13 Mar 2014

Keywords

  • Jointed rock masses
  • Plucking
  • Plunge pool
  • Rock riverbed
  • Scour hole
  • Uplift

Fingerprint Dive into the research topics of 'Mechanics and response of a surface rock block subjected to pressure fluctuations: A plucking model and its application'. Together they form a unique fingerprint.

Cite this