| Summary: | 博士 === 國立臺灣科技大學 === 營建工程技術學系 === 83 === Granular materials, such as soil, rock, concrete, ceramic,
etc., are most commonly used in civil engineering. Upon
loading, those materials are characterized by the
anisotropic behavior, the volumetric contraction or
dilation, the sensitivity to the hydrostatic pressure and
the irreversible loading/unloading process. The general
classic mechanics which is based on the continuum
assumption can not analyze correctly their material
properties. An analytical model that breaks the
continuum assumption of mate Considering the variation of
stress-strain distribution in granular materials, this
paper proposes two analytical models: the first, based on
the assumption of uniform distribution of strain field to
derive the constitutive laws for granular materials, is termed
the Kinematics model; the second, based on the uniform
distribution of stress variation for the constitutive
derivation is termed the Equilibrium model. From the
microscopic point of view, the failure of interface
between particles generally cause According to the
assumption of an isotropic and homogeneous material, it can be
proved that the two models get same results for the stress-
strain relations as those obtained from the linear
elasticity. For nonuniform arrangement of particles in
granular materials, the elastic behavior predicted by the
Kinematic model is much stiffer than that from the
Equilibrium model. The stiffness obtained from the static
analysis for a real packing of granular materials falls
between these two limiting values from
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