Engineering Rock Mechanics

(Jacob Rumans) #1
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lncllnatlon of dlscontinuity normal to major principal stress axis
example, the influence of the fractures on rock mass strength which we
have highlighted in this chapter has been extended7 by Amadei (1988)
to 3-D and to include the effect of the intermediate principal stress.
When a rock mass is loaded, as in Fig. 8.5, we are interested in the
manner in which it will deform, how much it will deform, when failure
will occur, and what will happen after failure. Similarly, if an excavation,
such as a tunnel, is created in the rock mass, we are interested in the
same factors. But, because of the complexity of the rock mass and the
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Figure 8.5 Load applied to a rock mass.
7Amadei B. (1988) Strength of a regularly jointed rock mass under biaxial and
axisymmetric loading. Int. J. Rock Mech. Min. Sci., 25, 1, 3-13.

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