In advance longwall mining, the safety of mine network, production rate, and consequently, economic conditions of a mine are dependent on the stability conditions of gate roadways. The gate roadway stability is a function of two important factors: 1) characteristics of the excavation damaged zone (EDZ) above the gate roadway and 2) loading effect due to the caving zone (CZ) above the longwall w...

In the context of nuclear waste disposal in clay formations, laboratory experiments were performed to study at reduced scale the Excavation Damaged Zone (EDZ) induced by the construction of galleries in the Boom Clay formation. For this purpose, thick-walled hollow cylindrical samples were subjected (after recovery of in-situ stress conditions) to a decrease of the inner confining pressure aimi...

Excavation of the galleries for geological disposal radioactive waste can induce an excavation damaged zone (EDZ), which have consequences on long-term safety repository. In this study, intact Callovo-Oxfordian (COx) claystone taken from Meuse/Haute-Marne Underground Research Laboratory in France was artificially fractured different directions, and hydro-mechanical behaviour investigated by per...

Deep geological repository is the preferred solution in many countries to manage radioactive wastes, such as France where Callovo-Oxfordian (COx) claystone candidate host rock. In clay rock formation, drilling of storage gallery creates an Excavation Damaged Zone (EDZ) with altered flow properties short term, while corrosion processes release large amounts gas long term. Assessing evolution pre...

An accurate theoretical model to predict the extent and mechanical behavior of excavation damage zone (EDZ) in surrounding rock deep-buried tunnel is great importance for practical engineering applications. Using elastic-plastic theory combined with analysis on stress characteristics rock, this paper present a EDZ formation evolution. A three-zone composite was established surround correspondin...

The umbrella-shaped bolt (U-bolt) is a novel type of mechanical used for rock reinforcement. It made smooth steel bar, hinges, rigid rods, and sliding blocks. During installation operation, the tension converted into extrusion force on mass deep in slope, so that higher compressive strength to obtain greater friction anchoring force. In this article, structural analysis results U-bolt provided,...

Abstract. Construction of cavities in the subsurface is always accompanied by excavation damage. Especially context deep geological nuclear waste disposal, evolving damaged zone (EDZ) near field emplacement tunnels utmost importance concerning safety aspects. As EDZ differs from intact host rock due to enhanced hydraulic transmissivity and altered geomechanical behavior, reasonable location-dep...

To better understand the coupled thermo-hydro-mechanical processes in Callovo-Oxfordian (COx) claystone formations induced by heat emitting high-level radioactive waste, different scales of in-situ heater experiments have been conducted ANDRA Meuse/Haute-Marne Underground Research Laboratory (M/HM URL) at Bure France. In order to prove predictability numerical codes for a site-scale repository,...

This study is aimed at investigating the excavation damage characteristics of surrounding rock in Jinping deeply buried marble tunnels, China. According to acoustic detection results tunnel cross-sections under condition boring machine (TBM) obtained on site, PFC microscopic parameters Types II/III were simulated and calibrated through PFC2D program. In doing so, deeply-buried sections diversio...

One of the methods used to investigate the damaged zone in rock structure is the acoustic emission method. This method is based on receiving the elastic waves that are produced by deformation and cracking of the rock mass around the underground excavation. In this research, a study is conducted on the rock samples by a numerical method to investigate the damaged zone caused by the excavat...