In situ rock stress
4
4.1 The nature of in situ rock stress
Having explained the concept of stress in Chapter 3, we now consider
why there is a natural stress state in the rock and some of the key aspects
of the subject, especially measuring the in situ stress and predicting
variation in the stress state from point to point in a rock mass. In
Chapter 5, we will consider the concept of strain and how stress and
strain can be linked.
Six independent components are required to specify the stress state
at a point. The stress state can be presented as the matrix of stress
components relative to specified x, y and z reference axes.
/
f&Right-handed
co-ordinate
system
or in principal stress form