Study of the experience in operating hydraulic tunnels

The excavation disturbed zone (EDZ) at Kiirunavaara mine, Sweden—by seismic measurements

“…The EDZ is generally defined as the zone beyond the excavation boundary where the rock has been considerably disturbed and/or damaged due to the excavation and re-distribution of stresses, see for example, Fairhurst and Damjanac (1996), Martin et al (1997), Martino and Chandler (2004), Tsang et al (2005), Mostkov (1979), Fishman and Lavrov (1996) among others. The disturbance and damage are mainly in the form of creation of new fractures, closure and opening of preexisting fractures (Sato et al, 2000), and disturbance of the in situ stress (Tsang et al, 2005).…”

Hybrid Finite-Discrete Element Modelling of Blast-Induced Excavation Damaged Zone in the Top-Heading of Deep Tunnels

“…The disturbance zone with properties and conditions irreversibly changed is often referred to as Excavation Damaged Zone (EDZ) or the Damaged Rock Zone (DRZ) [2,3]. Significant efforts have been spent worldwide in gaining an understanding of EDZ over the last few decades, especially characterizing and classifying EDZ [3], which includes the studies on EDZ around hydraulic tunnels in Russia [4] and that around in the Three Gorges Dam in China [5,6], and several international workshops on EDZ [2,7]. Nowadays, the fast development of the computer technology makes it become possible to complete large-scale numerical calculations in a short time.…”