Although healthy dentin is invariably hydrated in vivo, from a perspective of examining the mechanisms of fracture in dentin, it is interesting to consider the role of water hydration. Furthermore, it is feasible that exposure to certain polar solvents, e.g., those found in clinical adhesives, can induce dehydration. In the present study, in vitro deformation and fracture experiments, the latte...

Intermittent fluid pulses in the Earth’s crust can explain a variety of geological phenomena, for instance the occurrence of hydraulic breccia. Fluid transport in the crust is usually modeled as continuous Darcian flow, ignoring that sufficient fluid overpressure can cause hydraulic fractures as fluid pathways with very dynamic behavior. Resulting hydraulic fracture networks are largely self-or...

An experiment was conducted to demonstrate the utility of quantitative fracture flow visualization techniques in the study of entrapped fluid phase (air) dissolution into a flowing phase (water) within a horizontal, transparent, analog rough-walled fracture. The fracture aperture field and phase occupancy were measured using light transmission techniques and then combined to calculate bulk wate...

This paper documents our effort to use a fully coupled hydro-geomechanical numerical test bed to study using low hydraulic pressure to stimulate geothermal reservoirs with existing fracture network. In this low pressure stimulation strategy, fluid pressure is lower than the minimum in situ compressive stress, so the fractures are not completely open but permeability improvement can be achieved ...

[1] A single plane fracture with an axially symmetric stress distribution behaves as a seismic lens that focuses seismic energy to a beam ‘‘waist’’ at a focal plane. Both phase and amplitude effects on a seismic wave propagating across the fracture contribute to the lensing behavior. Radial gradients in the fracture specific stiffness cause wave refraction through a radially varying group time ...

Mechanical testing of collagenous tissues at different length scales will provide improved understanding of the mechanical behavior of structures such as skin, tendon, and bone, and also guide the development of multiscale mechanical models. Using a microelectromechanical-systems (MEMS) platform, stress-strain response curves up to failure of type I collagen fibril specimens isolated from the d...

A hydro-mechanical approach is developed to investigate progressive fracture damage study with flow behavior in PMMA sample. A series of experiments are conducted to replicate the field work of hydrofraturing process. The PMMA (poly methyl methacrylate) specimens have been performed to simulate to fracture developments that are similar to hydrofraturing process. These Fractures are mechanical b...

For optimal hydrocarbon recovery from fractured reservoirs, a critical issue is to gain an accurate understanding of the natural fracture system. Currently, fracture characterization using amplitude based technologies is routinely performed relying on amplitude versus angle/offset (AVA/AVO) and azimuth (AVAZ) to exploit anisotropic gradient behavior, which is today commonly used in the industry...

In this investigation the fracture resistance of scales from Cyprinus carpio was evaluated as a function of environmental temperature. Tear specimens were prepared from scales obtained from three characteristic regions (i.e. head, mid-length and tail) of multiple fish. The fracture resistance was characterized in Mode III loading and over temperatures ranging from -150°C to 21°C. Results showed...