correct estimation of water inflow into underground excavations can decrease safety risks and associated costs. researchers have proposed different methods to asses this value. it has been proved that water transmissivity of a rock joint is a function of factors, such as normal stress, joint roughness and its size and water pressure therefore, a laboratory setup was proposed to quantitatively m...

Bone fracture due to an accident, aging or diseases is a feature of everyday life. One of the principal methods of repair and reconstruction of such a fracture is based on drilling the bone and fixing its separate parts together using screws, wires and plates. Morphology of the drilled hole surface and fixative components such as screws, pins and hooks influences strength of the bonds between t...

OBJECTIVES To assess the effect of interfacial surface roughness on the flexure strength and fracture mode and origin utilizing an in-vitro assessment of the clinical failure conditions expected for all-ceramic crowns and the connector area of fixed partial dentures (FPDs) using bilayered ceramic specimens tested in bi-axial flexure. METHODS Sets of 20 bilayered composite discs, with core:den...

Abstract In the hydraulic fracturing process of shale reservoir, proppant will embed and deform under action high closure stress. Thus, it is necessary to analyze mechanical influencing factors embedding in shale. This study reproduced rough fracture surface real rock slabs based on reverse reconstruction method obtained parameters slab proppant. this study, a numerical model for elastoplastic ...

fault zones and fault-related fracture systems control the mechanical behaviors and fluid-flow properties of the earth’s crust. furthermore, nowadays, modeling is being increasingly used in order to understand the behavior of rock masses, and to determine their characteristics. in this work, fault zones and fracture patterns are reviewed, and also comprehensive studies are carried out on the fr...

We introduce a discrete element simulation for the hydraulic fracture process in a petroleum well which takes into account the elastic behavior of the rock and the Mohr-Coulomb fracture criterium. The rock is modeled as an array of Voronoi polygons joined by elastic beams, which are submitted to tectonical stresses and the hydrostatic pressure of the fracturing fluid. The fluid pressure is trea...

numerical methods such as boundary element and finite element methods are widely used for the stress analysis in solid mechanics. this study presents boundary element method based on the displacement discontinuity formulation to solve general problems of interaction between hydraulic fracturing and discontinuities. the crack tip element and a higher order boundary displacement collocation techn...

The optimal design of production in fractured geothermal reservoirs requires knowledge of the resource’s connectivity, therefore making fracture characterization highly important. This study aims to develop methodologies to use resistivity measurements to infer fracture properties in geothermal fields. The resistivity distribution in the field can be estimated by measuring potential differences...

We describe a theoretical model of the fluid flow, heat transfer and phase change which occurs when liquid is injected into a fracture bounded by a hot, impermeable rock. We first consider the case of a warm host rock, in which there is no boiling of the water. We then develop the model to describe the case in which the host rock temperature is in excess of the boiling temperature and the water...