... tangential stress equation 13th international congress maximum principal stress principal stress stress precondition precondition tunnel rock mechanics isrm13 STRESS-TO-STRENGTH CHARACTERISTICS OF BRITTLE FAILURES AROUND UNDERGROUND EXCAVATION OPENINGS *C. Wang, and R. Wang Key Laboratory...

... the measure of the minimum principal stress ( s 3 ) and the level when the occurrences ceased represents the measure of the maximum principal stress ( s 1 ). Therefore, this test of cheap and simple performance is able to measure the magnitude of the minimum and maximum principal stresses, allowing...

... is in a compression state similar to a sample in a triaxial test. The maximum principal stress in the wedge A ( 1A) is equal to the stress transmitted by the foundation (q) if the weight of the rock is not considered. Wedge B is also under a stress state similar to the one presented in a triaxial test...

... stress and strain to all elements according to a procedure how to trans- form from nodal displacement. Figure 3 shows deformation modes and the distribution of a maximum principal stress in lower modes from the 1st mode to the 5th mode. Each dis- placement and principal stress is the relative value...

... Technique, the Hydraulic Fracturing Method, and the Aooustic Emission Method. The results obtained are harmoniouSwith each other, and the magnitude'of the maximum principal stress has been evaluated to be about 26MPa. This is much larg~r than the stresses measured previously at another construction sites...

... Fairhurst variation certain water pressure level hydraulic fractured borehole hydraulic fracturing displacement borehole fluid flow principal stress Upstream Oil & Gas maximum principal stress contribution stress field equation numerical study stress ratio crack length water...

..., JDC Corporation, Tokyo, Japan .' "'I I' I' 'I ABSTRACT: The authors carried out laboratory experiments using cubic specimens of mortar in order to seek the possibility of direct measurement of the maximum principal stress from the shut-in pressure data by making a (pair of) artificial longitudinal...

... some conclusions are drawn as follows: 1) The stresses operating in the mine district are predominantly horizontal, compressive stresses which agree with the results of the survey of engineering geology and drift deformation carried out in the mine. 2) The maximum principal stress near the surface...