METHOD TO DETERMINE STRESSES IN ROCK MASSIF Russian patent published in 2013 - IPC E21C39/00 

FIELD: mining.

SUBSTANCE: method is based on using an acoustic emission memory effect in composite materials. A measurement device is formed by means of installation of two packets in a measurement well, between which epoxide resin is injected with a hardener and a filler of quartz sand. After resin hardening and completion of massif recovery deformations, the device is drilled with a circular slot, removed from the massif and cut into even discs. Produced discs are tested at press equipment under conditions of uniaxial compression with simultaneous registration of total count of impulses of acoustic emission, besides, each subsequent disc is turned by a fixed angle. As a result of tests the dependence is identified with maximum increase of acoustic emission count speed steepness as a certain level of test load is achieved, and on the basis of this level the maximum stress available in the massif is identified, and on the basis of the disc rotation angle the azimuthal angle of the specified stress action is determined.

EFFECT: higher accuracy and reduced labour intensiveness of detection of value and direction of maximum stress in a massif, acting in plane of orthogonal axis of a measurement well.

4 dwg