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The layered structure of slate rock induces strength anisotropy. The strength in the direction of the layers (schistosity) is considerably smaller than in any other direction. A series of loading tests on circular samples and another series of loading tests on rectangular samples are performed to examine fracture patterns in slate. The tests are monitored by visual recordings and by recording acoustic emission. The processing of this data results in localization. This allows identification and analysis of the occurrence and propagation of the individual fractures. It is shown that the strength anisotropy on µ-scale is the key factor behind the strength anisotropy on sample scale, as well as behind the deformation behaviour of the sample. In addition, it is observed that a small variability in the layer direction can affect the fracture pattern considerably.

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The structure of the surface layer of the soil is strongly influenced by soil tillage practices, with important consequences for the hydraulic properties and soil moisture dynamics in the top soil layer. In this study, during four 28‐d periods, we monitored L‐band brightness temperatures and infrared (IR) temperatures over bare silt loam soil plots with different soil surface structure: tilled, seedbed, and compacted plots. Differences in absolute and normalized L‐band brightness temperatures between the plots indicated that plot specific roughness, soil moisture contents, and soil hydraulic properties might be inverted from L‐band brightness temperatures using a coupled radiative transfer, roughness correction, and soil hydrological model. The inversely estimated surface roughness parameters compared well with those derived from laser profiler measurements. The estimated saturated water contents of the tilled and seedbed plots were larger than the one of the compacted plot, and the unsaturated hydraulic conductivity was smaller in the former plots than in the compacted plot for more negative pressure heads. These differences in hydraulic properties translated into larger dynamics of the simulated soil moisture during a 28‐d measurement period in the tilled and seedbed plots than in the compacted plot. This difference could be confirmed qualitatively but not quantitatively by in situ soil moisture measurements. Furthermore, differences in simulated actual evaporation rates between the plots were confirmed by observed differences in measured IR temperatures. The results indicate that effects of soil management on soil surface roughness and soil hydraulic properties could be inferred from L‐band brightness temperatures.

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Abstract. ANDRA (Agence Nationale pour la Gestion de Déchets Radioactifs) has developed an integrated approach to characterizing the hydrogeology of the carbonate strata that encase the Callovo-Oxfordian argillite at the Meuse/Haute-Marne Laboratory site. The argillites are difficult to characterize due to their low permeability. The barrier properties of the argillites can be inferred from the flow and chemistry properties of the encasing Oxfordian and Dogger carbonates. Andra's deep hole approach uses reverse air circulation drilling, geophysical logging, flow meter logging, geochemical sampling, and analyses of the pumping responses during sampling. The data support numerical simulations that evaluate the argillite's hydraulic behaviour.

A method for localization by acoustic emission in transversely isotropic media is developed and validated. Velocities are experimentally measured and then used to calculate a database of theoretical arrival times for a large number of positions. During an actual test, positions are assigned by comparing measured arrival times with the database's arrival times. The method is applied during load tests on slate samples and compared with visual observations of fractures. The localization method allowed for a good identification of the regions of fracturing at different stages during the test.

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