Open AccessApplication of rate‐and‐state friction laws to creep compaction of unconsolidated sand under hydrostatic loading conditions
Author(s) -
Hagin Paul,
Sleep Norman H.,
Zoback Mark D.
Publication year - 2007
Publication title -
journal of geophysical research: solid earth
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.67
H-Index - 298
eISSN - 2156-2202
pISSN - 0148-0227
DOI - 10.1029/2006jb004286
Subject(s) - creep , hydrostatic equilibrium , geotechnical engineering , compaction , geology , strain rate , deformation (meteorology) , hydrostatic pressure , stress (linguistics) , fault (geology) , overburden pressure , materials science , law , mechanics , composite material , seismology , linguistics , oceanography , physics , philosophy , quantum mechanics , political science
Rate‐and‐state variable friction laws describe the time‐dependent fault‐normal compaction that occurs during holds in slide‐hold‐slide friction tests on unconsolidated materials. This time‐dependent deformation is qualitatively similar to that observed during volumetric creep strain tests on unconsolidated sands and shales under hydrostatic loading conditions. To test whether rate‐and‐state friction laws can be used to model volumetric creep processes in unconsolidated sands, the rate‐and‐state formulation is expanded to include deformation under hydrostatic stress boundary conditions. Results show that the hydrostatic stress form of the rate‐and‐state friction law successfully describes the creep strain of unconsolidated sand. More importantly, values obtained for rate‐and‐state friction parameters by fitting these data are in the same range as those obtained from more traditional tests by fitting the fault‐normal compaction of simulated gouge during a hold in a laboratory friction experiment.