Questions 4.1 -4.1 0:
in situ rock stress
- I There is no internationally agreed terminology for words describ-
ing the state of stress in a rock mass. However, describe in one sentence
what you think is meant by each of the following terms.
Natural stress Thermal stress
Induced stress Palaeostress
Gravitational stress Near-field stress
Tectonic stress Far-field stress
Residual stress Local stress
44.2 Add the following 2-D rock stress states, and find the principal
stresses and directions of the resultant stress state.
44.3 How many experimental set-ups are required to determine the
3-D state of stress in a rock mass, using each of the standard stress
measurement methods of flatjack, hydraulic fracturing, USBM gauge
and CSIRO gauge? (Assume that the stress field is constant in the
vicinity of the test site.)
44.4 Three flatjack tests have been
made close to each other in the wall
of a long, straight tunnel, the axis
of which dips at 7". The measure-
ment position is approximately 250 m
below the ground surface and it is
assumed that the flatjacks are in the
same stress field. The slots for the flat-