... Hmax values slightly higher than the vertical stress (S v ) and the minimum horizontal principal stress (S hmin ) possibly lower than S v , suggesting that the stress state is predominantly in favor of strikeslip faulting. strength mbsf breakout compressive failure reservoir geomechanics...

... as performance of hydraulic stimulation. stress model Reservoir Characterization borehole observation borehole breakout exp-1 hole reservoir geomechanics orientation Finland Johansson Rock mechanics Rock stress estimation stress measurement fracture Upstream Oil & Gas strength...

... projects. This study concerns the rock-burst problems encountered in the deepest and larger of the Carrara Marble underground quarry: the Carlone quarry. reservoir geomechanics strength stress state Carlone quarry Upstream Oil & Gas quarry MPa Reservoir Characterization rockburst...

... Chinese Journal correlation stability stress measurement principal stress Reservoir Characterization Engineering cavern rock cavern Rock stress reservoir geomechanics strength deformation rock burst Rock mechanics rock breakdown pressure breakdown pressure tunnel Rock Stress...

... geomechanics borehole compressive strength maximum horizontal horizontal principal stress real time system strength sandstone real-time monitoring tunnel maximum horizontal principal stress in-situ stress measurement rock burst burst-prone tendency principal stress Magnitude Rock Stress...

... from the most recent hydraulic stress measurements at the Olkiluoto site, Finland (Fig. 1), are presented. Upstream Oil & Gas strength MPa hydraulic fracturing orientation borehole Reservoir Characterization tensile failure criterion borehole wall shear stress determination...

..., concentrated on the floor, on the one hand, the floor rock expansion and deforma- tion will take place and resulting in swelling stress, on the other hand the rock strength will be weaken and the destruction of floor rock will be exacerbated, which is a major cause of roadway damage. Figure 2. Picture...

... in situ horizontal stresses are kept in intact gneiss, with unaxial strength more than 45 MPa and overburden more than 200 m. The large subhorizontal in situ stress mainly plays the role of 2 during tunnel excavations in the section of gneiss with severe rockbursts occurred. The initial stress...

...) and Peru (Windsor, 2009a) in attempts to reconcile the stress measurement results with local conditions of rock strain, rock structure and rock strength. Here, we record the scalar characteristics (ie stress magnitudes alone) from ca. 200WASMAE rock stress tensor determinations obtained from different...

... interpreting results from stress measurements using stress relief techniques, one funda- mental assumption is that the rock behaves elastically. This assumption may not be verified if the stress level to which the recovered core is submitted surpasses its strength. Local shear or tensile yielding may occur...

... that to spread the fissure. The pore pressure in rock results in the decrease of the tensile strength. Cylinder specimens were directly tensile under confining, hollow cylinders were fractured by inner pressure under different axial load, and rings were Brazilian split. The experimental results show that two...

... ABSTRACT: Silt mudstone lied in deep field underground is the immediate roof of roadway and coal mining face, which mechanical properties may be important to corresponding engineering. By uniaxial mechanical test in laboratory for rock specimens, average instantaneous ultimate strength...

... with concentrated stress near the chamber wall. Elastic strain energy stored in the rock mass will release suddenly with impetuous unstability damage for rock mass when stress exceeds breaking strength of rock mass. Broken rocks will eject on the chamberwall or a lot of rocks will outburst to generate violent blast...

... model of Mohr-Coulomb (MC) and strain hardening & softening (SS) were taken as a comparison, variation of geologic factors, such as dip angle, strength, thickness and depth of rock stratum, were done. It was verified that bedding slip formed by the application of horizontal in-situ stress...

... stress west wing track roadway metals & mining strength mechanism roadway stress field serious floor heave Rock Stress and Earthquakes Xie (ed.) © 2010 Taylor & Francis Group, London, ISBN 978-0-415-60165-8 Mechanism and support measures of floor heave mainly caused by horizontal...

..., China Yan Xiangzhen, Yang Xiujuan College of Storage & Transportation and Architectural Engineering, China University of Petroleum, Dongying, Shandong, China ABSTRACT: Calculation formulas of geological strength index(GSI) and jointing parameter(JP) of rock strength index(RMi) are derived, and the GSI...

... at different scales. From Weibull theory it is believed that the increase in scale causes a decrease in the strength. This has been quantified by the Hoek-Brown equation for Uniaxial Compressive Strength (UCS). However, the confinement can change this strength and subsequently yielding. Thus, from experimental...

... Engineering resistance syncline axis structural geology strength Rock mechanics deep rock roadway failure mechanism truss deformation flexible layer truss Anchor deformation energy Rock Stress and Earthquakes Xie (ed.) © 2010 Taylor & Francis Group, London, ISBN 978-0-415-60165-8 Failure...

... shizishan copper mine is up to 1100m and many coal mines will enter into the depth of 1000∼1500m (Zhou & Xie 2005). metals & mining deformation failure characteristic reservoir geomechanics strength stability MPa Reservoir Characterization structural geology stress field Geostress...

... ABSTRACT: This paper describes longwall numerical model of Tabas Coal Mine (Iran) by using commercial code FLAC3D. The coal seam was modeled as strain softening material and its parameters were established by calibrating separate test pillar models to common empirical pillar strength formulas...