On large slides where access to the slope is hazardous and
there is a need to make frequent and precise measurements and rapidly analyse
the results, surveying is the most suitable monitoring method. There are three
components of a survey system.
One or several reference points on stable ground, which
can be viewed from the instrument stations closer to the slide.
A number of instrument stations set up on reasonably
stable ground at locations from which the slide is visible. If the
co-ordinate positions of the movement stations are to be measured, then the
instrument stations should be arranged such that they form an approximately
A series of stations set up just outside the slide area,
located relative to the instrument stations. It is preferable that the
measurement direction be in the likely direction of movement so that the
distance readings approximate the actual slide movements.
Figure 13: Survey
system to remotely measure slope movement