A NEW PERMANENT-INSTALLATION DEVICE FOR MONITORING STRESSnCHANGES IN NX CORE HOLES

摘要

A solid-inclusion probe has been developed to monitor stress changes in rock. The probe is designed for use in NX-sized drill holes and it can detect stress changes from 0 to 5,000 pounds per square inch from a few milliseconds to a few years in the time domain. These probes have been used to monitor the dynamic stresses of low-yield nuclear detonations at a distance of a few hundred feet and they have remained operable during and after the detonations.