A ROCK ANCHOR LOAD INDICATOR

摘要

The invention relates to a rock anchor. The invention provides a warning device for use in conjunction with a rock anchor. The warning device includes compressible means (34) formed to be installed on a rock anchor in a configuration in which a tensile force operatively exerted on the rod (18) of the rock anchor by a surrounding rock formation is transferred to act as a compressive force on the compressible means (34). The warning device includes also indicator means (36, 110) for indicating when a predetermined magnitude of compressive deformation of the compressible means (34) has operatively occurred. Such deformation may be indicative of a movement within the rock formation. In one embodiment, the indicator means is entirely mechanical. The warning device may be configured to operatively indicate more than one predetermined magnitude of compressive deformation of the compressible means.