... ABSTRACT: The paper presents a methodology developed to determine the spatial "debris-flow initiation hazard". Through the field study of twelve catchments prone to debris flows in the French Alps and the laboratory analyses of many samples of debris-flow deposits and source-area materials...

...LABORATORY EXPERIMENTS ON INITIATION OF RAINFALL- INDUCED SLOPE FAILURE WITH MOISTURE CONTENT MEASUREMENTS Adrin Tohari1, Makoto Nishigaki1, and Mitsuru Komatsu1 ABSTRACT A series of laboratory slope failure experiments was conducted to elucidate the initiation of rainfall-induced slope failures...

... initiation, secondary cracking and crack coalescence thresholds, crack development thresholds marking the initiation and/or opening of cracks. Results also suggest that in tests where elements of time are considered in the loading process, a significant percentage of brittle fracture damage can occur during...

... tunnel in limestone many times. In adit no. 2, the extent and depth of f'a iLu.:e in the surrounding rock and burst intensity increase with increasing buried depth of the adit. The observed data show that the initial stress in rock mass is not necessarily the gravitational stress field. However...

... MPa. '!he results showthat during the brittle fracture of sarrlstone both P-wave= S-wavevelocity initially increase during closure of pre-existing cracks an::ipores, . . ~en decrease during dilatant microcracki.rg. 'Ihe acoustic emission event rate is ~tJ.ally very low during quasi-elastic defomation...

... (ratio of amplitude to frequency of AE) and AE energy (square of amplitude of AE) are available to detect the initiation of small-scale failure of rock, i.e., the loosening of rock mass around opening. 1 INTRODUCTION The construction of large and deep under- ground openings such as gas storage caverns...

... of discing, highlight the repetitivness in shape of discs. horizontal load horizontal stress Poisson stress direction Reservoir Characterization Maury investigation inclination horizontal principal stress situ stress direction principal stress Upstream Oil & Gas initiation geometry...

... field and large scale geological structure, and to obtain data for the assessment of earthquake risk. Initial efforts made use of overcoring techniques (United States Bureau of Mines (USBM) borehole deformation gauge and the CSIRO hollow inclusion cell) near to the surface (generally less than 5 metres...

... Abstract: A two-dimensional elastic analysis is made of conditions for initiating} by pressurizing a Jacketed borehole, secondary fractures that extend perpendicular to the maximum In-situ stress, σ 1. The problem is uncoupled into two parts: first, the tangential stress IS calculated...

... and propagation of macro- scopic cracks which result in the formation of a coarse chipe. After the formation of that coarse chip, the continuing progress of the tool finely crushes a peak of the rock that remained in the lower part of the crack initiation point, as shown in Fig.l, b. This is called secondary...

...The initiation and detection Proceedings of the International Symposium on Weak Rock / Tokyo /21·24 September 1981 of discontinuities in a continuum HANS VAN DER KOGEL Delft Soil Mechanics Laboratory, Netherlands 1 ABSTRACT The outlined theory forms the framework for detecting an initiation...