Ceramic coatings deposited on metal substrates generally develop significant compressive stresses when cooled from the temperature at which they are processed as a result of thermal expansion mismatch. One of the main failure modes for these coatings is edge delamination. For an ideally brittle interface, the edge delamination of a compressed thin film involves mode II interface cracking. The c...

A sound knowledge of mechanical properties of rocks at high temperatures and pressures is essential for modelling volcanological problems such as fracture of lava flows and dike emplacement. In particular, fracture toughness is a scale invariant material property of a rock that describes its resistance to tensile failure. A new fracture mechanics apparatus has been constructed enabling fracture...

The paper deals with a shape of geological discontinuities. This significantly affects the stability rock massifs. joint roughness coefficient (JRC) is one main indicators but methods its estimation are based on empirical analysis fracture curves in present. We propose new mathematically correct theory automatic JRC. It shows that determination JRC should be not only subjective experience, obje...

Abstract To understand the influence of temperature on flow characteristics fractured granite, high-temperature cyclic thermal treatment and tests rock sample with different joint roughness coefficients intact samples were conducted. The larger confining pressure coefficient will increase resistance fluid affect fluid. With increasing, aperture fractures, number micro-fractures, micropores whic...

Fluid pressure inside a borehole produces hydraulic fracture and damage zones in the vicinity of the borehole. These fractures result from stress concentrations around the borehole. The results of numerical simulation of a borehole subjected to fluid pressure using a micromechanical damage model [2] are presented in this paper. It is observed that tensional concentrated stresses are generated a...

A recognized issue related to metal-on-metal hip resurfacings is early fracture of the femur. Most theories regarding the cause of fracture relate to clinical factors but an engineering analysis of failed hip resurfacings has not previously been reported. The objective of this work was to determine the wear volumes and surface roughness values of a cohort of retrieved hip resurfacings which wer...

Natural fractures are important conduits for fluid-flow and can control the deformational behavior of rock. The accurate evaluation of natural fracture geometry in the subsurface is difficult because of the sampling problems inherent to wellbores and indirect investigation methods such as seismic. Because of these limitations in observational capability, predictive models are needed to provide ...

The concept of brittleness plays a crucial role in the development of tight oil and gas as it reflects a rock’s ability to fail and maintain a fracture in a hydraulic fracture experiment. Conventional methods that attempt to quantify the degree of brittleness associated with a rock mass have a few shortcomings. For example, failure criteria are not used and only the effective moduli are conside...

We briefly review the models of fracture dissolution process, discussing the experimental and numerical evidence showing that this phenomenon is inherently two-dimensional and hence cannot be accurately described by one-dimensional models. The physical reason for this incompatibility is that a dissolution front in a single rock fracture is potentially unstable to small variations in local perme...

Mechanisms for fatigue crack closure under plane strain conditions have recently been identified at very low (near-threshold) stress intensities in terms of effects of excess corrosion deposits or fracture surface roughness in promoting premature closure of the crack. In the present paper, a geometric model is presented for crack closure induced by fracture surface roughness. This model specifi...