Standards Development

Scope

This document specifies the measurement of displacements by means of geodetic instruments carried out for geotechnical monitoring. It refers to position measurements where a signal travels through air/the atmosphere between an instrument and a measuring point (target). General rules of performance monitoring of the ground, of structures interacting with the ground, of geotechnical fills and of geotechnical works are presented in ISO 18674‑1:2015.

This document is applicable to measurements carried out for monitoring purposes by means of:

— tachymeter (manual or robotic );

— level;In informative annexes, this document also refers to principles of some techniques that are commonly used for the monitoring of displacements of topographic surfaces:

— satellite Interferometric Synthetic Aperture Radar (InSAR);terrestrial radar interferometry;

— laser scanning;

— GNSS.

NOTE 1: This document fulfils the requirements for the performance monitoring of the ground, of structures interacting with the ground and of geotechnical works by the means of geodetic instruments as part of the geotechnical investigation and testing in accordance with References [1] and [2].

NOTE 2: A key element of any and all monitoring is the ability to reflect the reality of what one intends to measure. There is a wide discrepancy and disagreement between the terms used to call this ability, depending on the field of application and country of origin.

ISO/IEC guide 99:2007 defines terms for measurements of one quantity values, whereas in monitoring we generally try to measure change between quantity over time.

The terms approaching best our needs in ISO/IEC seems to be “Precision” and “Uncertainty”.