scope:

This document specifies the measurement of displacements along aline by means of extensometers carried out for geotechnicalmonitoring. General rules of performance monitoring of the ground,of structures interacting with the ground, of geotechnical fillsand of geotechnical works are presented in ISO 18674-1. If appliedin conjunction with ISO 18674-3, this document allows thedetermination of displacements acting in any direction. Thisdocument is applicable to: ? monitoring the behaviour of soils,fills and rocks; ? checking geotechnical designs in connection withthe Observational Design procedure; ? deriving geotechnical keyparameters (e.g. from results of pile load tests or trialtunnelling); ? evaluating stability ahead of, during or afterconstruction (e.g. stability of natural slopes, slope cuts,embankments, excavation walls, foundations, dams, refuse dumps,tunnels). NOTE This document fulfils the requirements for theperformance monitoring of the ground, of structures interactingwith the ground and of geotechnical works by the means ofextensometers as part of the geotechnical investigation and testingin accordance with References [5] and [6].