We develop a finite-element method for the simulation of dynamic shell fracture and fragmentation based on cohesive models of fracture. We assume the shells to be thin and to obey the Kirchhoff-Love theory. The shell is spatially discretized by means of subdivision shell elements. Fracture is allowed only along element edges and is assumed to be governed by a cohesive law. When coupled to the s...

The hydraulic fracturing propagation is strongly influenced by the existence of natural fractures. This is a very important factor in hydraulic fracturing operations in unconventional reservoirs. Various studies have been done to consider the effect of different parameters such as stress anisotropy, toughness, angle of approach and fluid properties on interaction mechanisms including crossing, ...

Multi-horizontal well hydraulic fracturing is a widely employed and highly effective method for stimulating tight shale reservoirs. However, most existing studies primarily focus on investigating the impact of intra-well interference fracture propagation while neglecting influence inter-well interference. Here, multi-well hydraulic-fracture-propagation model established to examine effects withi...

a r t i c l e i n f o The purpose of this study is to investigate the role of filling materials (e.g., quartz sand and kaolin clay) in the interaction between a P-wave and a rock fracture. The specific fracture stiffness reflects the seismic response of a filled fracture, while the wave transmission coefficient describes P-wave transmission across the filled fracture. A series of experimental t...

This paper describes fractographic features observed in aerospace composites failed under tensile loads. Unidirectional Carbon Fibre Reinforced Plastic (UD CFRP) and Unidirectional Glass Fibre Reinforced Plastic (UD GFRP) composite specimens were fabricated and tested in tension. The morphology of fractured surfaces was studied at various locations to identify failure mechanism and characterist...

a frequency-wavenumber-domain formulation is presented in this paper for calculation of the green's functions and wave propagation modes in a stratified fluid body underlain by a layered viscoelastic soil medium. the green's functions define the solid and fluid displacements and fluid pressures due to uniform disk loads acting in either the soil or fluid media. the solution is in the frequency ...

The propagation of Stoneley waves in a fluid-filled borehole with a vertical fracture is investigated both theoretically and experimentally. The borehole propagation excites fluid motion in the fracture and the resulting fluid flow at the fracture opening perturbs the fluid-solid interface boundary condition at the borehole wall. By developing a boundary condition perturbation technique for the...

Introduction: The fracture mechanisms of bone tissue have been described as a damage accumulation process, which starts with the initiation and propagation of microcracks. Knowledge of crack initiation and propagation at tissue level (tissue fracture toughness) is critical to understand and prevent bone fractures. Tissue fracture toughness could provide valuable information for defining bone qu...

Stoneley waves in permeable boreholes are diagnostic of formation permeability because their propagation is affected by the dynamic fluid flow at the borehole wall. We characterize this flow using the concept of dynamic permeability. We examined the applicability of the dynamic permeability to porous media by applying it to a single fracture case and found that it agrees excellently with the fr...