In order to automate the scooping task, it is desirable that the resistive force acting on the bucket be obtained before the scooping is performed. The objective of this study is to derive theoretically the resistive forces acting on the bucket during scooping of piled rock fragments. First, the changes in the shape of the rock pile due to the penetration of it by the bucket are modeled. Based ...

The dielectric constant of a partially saturated sandstone varies as a function of the level of water saturation. Experimental data indicate that rock/water interaction, at low saturations, has a large effect on the measured dielectric response. To theoretically predict the dielectric constant of the rock/water/air system, this rock/water interaction must be accounted for by including the effec...

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...

Fluid flow in jointed rock mass with impermeable matrix is often controlled by joint properties, including aperture, orientation, spacing, persistence and etc. On the other hand, since the rock mass is made of heterogeneous and anisotropic natural materials, geometric properties of joints may have dispersed values. One of the most powerful methods for simulation of stochastic nature of geometri...

General e ective-stress rules are derived for various physical properties of inhomogeneous porous rocks. Some rigorous relations arising in the analysis show that the uid (pore) pressure pf is least e ective at counteracting the changes caused by con ning pressure for the solid (grain) volume; pf is more e ective for the total (solid plus pore) volume; pf is still more e ective for the pore vol...

This paper reports on the pressure dependence of the optical absorption edge of ZnO in the wurtzite and rock-salt phase, up to 14 GPa. Both vapor-phase monocrystals and pulsed-laser-deposition thin films have been investigated. In both types of samples the wurtzite to rocksalt transition is observed at 9.7G0.2 GPa. The absorption tail of the fundamental gap, as measured in monocrystals, exhibit...

Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. ABSTRACT The purpose of this paper is to test how well numerical calculations can predict transport properties of p...

Influence of air entrainment on rock scour development and block stability in plunge pools The impingement of high-velocity water jets on plunge pools, such as it occurs downstream of spillways of high-head dams, may cause scour on the rock foundations. The scour process is the result of complex and consecutive physical phenomena. Turbulence plays a major role, especially in the jet development...

The subject of this thesis forms part of a research program dealing with fractured rock masses being undertaken by the "Centre de Géologie de l'Ingénieur (CGI)" from the "Ecole Nationale Supérieure des Mines de Paris (ENSMP)" and the "Ecole Nationale des Ponts et Chaussées (ENPC)". In fractured rock masses, it is very difficult to undertake engineering works without analysing, beforehand, the f...