In 2000 and 2003, two massive hydraulic fracturing experiments were carried out at the European Geothermal Hot Dry Rock site at Soultz-sous-Forêts, France. The objective was to create a dense network of enhanced permeability fractures, which would form the heat exchanger. The injection of water in the fractured rock generated a high level of microseismic activity: around 30,000 and 90,000 micro...

Abstract. The purpose of the Wedge Splitting Test (WST) is to generate stable mode I fracture crack along a pre-established path, and be able to measure the specific fracture energy parameter of the material GF. The test is performed on standard cylindrical notched specimens. In order to make decision on the optimal notch geometry for a specific rock test, a number of WST experiments were simul...

Deep rock bears dynamic loads such as machinery, blasting and disturbance in the mining process. The fracture mechanism of deep is a necessary prerequisite for engineering design analysis. To study under high situ stress, mudstone sandstone were selected research objects. mechanical properties energy dissipation assessed by using 50 mm diameter separated Hopkinson test device. According to simi...

We study fracture of notched samples made of quasi-brittle, polyphase materials like rock, concrete or ceramics. The fracture demonstrates the size effect during loading. This means that a full-size sample made of such a material exhibits different fracture behaviour than a laboratory-size sample. The effect is explained by the existence of an extended zone of distributed defects and cracks (pr...

Fractured-rock aquifers display spatially and temporally variable hydraulic conductivity generally attributed to variable fracture intensity and connectivity. Empirical evidence suggests fracture aperture and hydraulic conductivity are sensitive to in situ stress. This study investigates the sensitivity of fractured-rock hydraulic conductivity, groundwater flow paths, and advectiondominated tra...

Water fluxes in unsaturated, fractured rock involve the physical processes occurring at fracture-matrix interfaces within fracture networks. Modeling these water fluxes using a discrete fracture network model is a complicated effort. Existing preprocessors for TOUGH2 are not suitable to generate grids for fracture networks with various orientations and inclinations. There are several 3-D discre...

The results form the application of the method of homogenization for the transport of solute in a porous medium with microscale pores and the rock matrix are applied to examine the dispersion characteristics of a solute in a porous rock matrix with parallel fractures including the retardation in the rock matrix and the decay effects. By using the solutions to a boundary value problem the effect...

Acoustic emission (AE), recorded during uniaxial compressive loading with constantly increasing stress and stepped increments until the fracture of prismatic marble specimens, were analyzed in terms non-extensive statistical mechanics (NESM). Initially introduced by Tsallis, NESM has proven to be an autonomous robust theoretical framework for studying mechanisms damage evolution processes exper...