A Continuum Damage-Breakage Faulting Model and Solid-Granular Transitions

摘要: We present a thermodynamically-based formulation for mechanical modeling of faulting processes in the seismogenic brittle crust using continuum damage–breakage rheology. The model combines previous results damage framework solids with breakage mechanics granular flow. accounts density distributed cracking and other internal flaws damaged rocks scalar parameter, addresses grain size distribution phase failure slip zone parameter. stress–strain relation kinetics are governed by total energy function system, which solid material. A dynamic instability is associated critical level solid, leading to loss convexity transition lower level. non-local provides an intrinsic length scale structure, leads finite localization that eliminates unrealistic singular local models. Shear heating during deformation can lead secondary finite-width localization. studying multiple aspects deformation, including potential feedback between evolving elastic moduli properties subsequent rupture behavior. has more general from slow than frictional sliding on single pre-existing zone, gives time scales onset fracturing process. Several features existence width rapid illustrated numerical simulations. configuration having existing narrow localized produces appropriate loading conditions overall cyclic stick–slip motion. simulated response includes transitions friction coefficient ~0.7 at low velocity below 0.4 rates above ~0.1 m/s, followed rapidly increasing ~1 m/s, consistent laboratory observations.