Relation between the shear and uniaxial strength of rock materials
The trap, in the translating formulation of the shear strength parameters(cohesion c, friction angle ϕ) and uniaxial strength parameters (tensile strength σt compressive strength σc) of rocks as Crude Kuroiwa, sandstone and etc., is discussed by comparing with the relative parameters measured from experiments. A statistical formula between the parameters of the deduced and measured uniaxial strength is represented, and a theoretical formula is derived and verified in the transmission process between the deduced and measured shear strength parameters.
Strength of rock-like materials
Abstract This paper deals with the strength of rock-like materials under triaxial stress conditions. The most common theories of brittle fracture are reviewed. Some methods of triaxial strength determination are described and the results compared. The strength dependence of lateral pressure, pore pressure and size of the test sample is described. Some standard tests are suggested. A method for determining the shear strength at high normal pressure has been used as a measure of the strength of a number of Swedish rocks and ores.
L-band 3D imaging of an Alpine Glacier: Results from the AlpTomoSAR campaign
In this paper we present results from the tomographic analysis of L-Band SAR data acquired in February/March 2014 over the Mittelbergferner glacier, Austrian Alps, during the ESA campaign AlpTomoSAR. The campaign includes coincident in-situ measurements of snow and ice properties, as well as high-frequency Ground Penetrating Radar (GPR) data acquired over a total length of 18 km. The analyses of three-dimensional TomoSAR data cubes shows the complexity of the glacier sub-surface scattering. Most areas are characterized by surface scattering in proximity of the Lidar surface, plus a complex pattern of in-depth volumetric scattering beneath. Various subsurface features observed in GPR transects at 600 MHz and 200 MHz clearly showed up in TomoSAR sections as well. In particular: firn bodies, crevasses, and even the bedrock down to 50 m below the ice surface.