Engineering Rock Mechanics
88 lnkrctrock convenient and can be established by unloading and reloading the specimen from any point on the curve. This is ill ...
Soft, stiff and servo-controlled testing machines 89 all costs, or to be encouraged, is a function of the engineering objective, ...
90 lntucfrock This situation can be considered as simply shortening the sample and measuring the associated load. The resultant ...
Soft, stiff and servo-controlled testing machines 91 of thinking of the machine stiffness is to consider its axial force+xtensio ...
92 lntact rock We arrive at the conclusion that if the testing machine stiffness is greater than the absolute value of the slope ...
Soft, stiff and servo-controlled testing machines 93 Error signal adjusted Electronic Experiment of Recording required indicatin ...
94 Intact rock Finally, it should be noted that the required experimental data can be monitored independently from the control s ...
Specimen geometry, loading conditions and environmental effects 95 Feedback 1-1 Beam test Compression F Feedback bit penetration ...
96 Intact rock It is well known that many materials exhibit a size effect in terms of strength, with smaller specimens indicatin ...
Specimen geometry, loading conditions and environmental ekcts 97 “t Size increases, strength decreases Figure 6.11 The size effe ...
98 Intact rock Slenderness increases, strength decreases Sample shape & Figure 6.12 The shape effect in uniaxial compression ...
Specimen geometry, loading conditions and environmental ekts 99 Axial stress I (‘a Uniaxial compression Qa Uniaxial tension Norm ...
100 lntact rock Frequency Aut) The tensile strength variation is of three main types: Brazilian test (a) variation with repeated ...
Specimen geometry, loading conditions and environmental effects 1 0 1 may be predicted. Indeed, the probability density function ...
1 02 htact rock Increasing confining pressure Ductile ____ Brittle Figure 6.15 The effect of confining pressure in the triaxial ...
Specimen geometry, loading conditions and environmental effects 1 03 6.4.4 Environmental effects Other factors which affect rock ...
104 Intact rock Time-dependent effects. We have indicated that during the complete stress-strain curve, microcracking occurs fro ...
Specimen geometry, loading conditions and environmental effecn 105 AK and BK which represent time-dependent unloading along the ...
106 Intact rock behaviour at a strain rate in the laboratory of 1 x and very much more ductile behaviour when undergoing tectoni ...
Failure criteria 107 traditionally regarded as the ‘cause’ and strain as the ’effect’ in materials testing: as a consequence, ea ...
«
1
2
3
4
5
6
7
8
9
10
»
Free download pdf