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The Hertz-Mindlin (HM) contact
model has been one of the most widespread
tool for numerical simulations on
granular matter behavior. Inter-granular
contact forces are predicted using
this approach relying on space distribution
of the grains and
the equation of motions are numerically
integrated. However, the basic assumptions
of this mean field approximation
have showed several pitfalls on
the elastic description of shear
phenomenon in granular packings.
In this work we present an acoustic
consistent contact model which scales
the tangential stiffness components
from the HM model. The scaling factors
are obtained by means of the numerical
and empirical ultrasonic multi-component
wave propagation comparison. Energy
partition between affine and non-affine
particle motion seemed to explain
the acoustic wave velocities differences
between HM simulations and laboratory
data. A pressure dependant HM pre-factor
is proposed to achieve more accurate
simulated results. This refined
model could give new insights on
rock mechanics modeling and hydrocarbon
seismic exploration.
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