Characteristics of an Excavation Damaged Zone developed around KAERI Underground Research Tunnel
The development of an excavation damaged zone, EDZ, due to a blasting impact and stress redistribution after an excavation, can influence the long term stability, economy, and safety of an underground excavation. In this study, the size and characteristics of an EDZ around an underground research tunnel, which was excavated by a controlled blasting, in KAERI were investigated. From in situ tests at KURT, it was possible to determine that the size of an EDZ was about 1.5m. Goodman jack tests and laboratory tests showed that the rock properties in the EDZ were changed by about 50％ compared to the rock properties before a blasting. The size and property changes in the EDZ were used for a hydro-mechanical coupling analysis. In the modeling, the rock strengths and elastic modulus in the EDZ were assumed to be decreased by 50％ and the hydraulic conductivity was increased by 1 order of a magnitude from the original values. From the analysis, it was possible to conclude that the displacement was increased while the stress was decreased because of an EDZ. When an EDZ was considered in the model, the tunnel inflow was increased by about 20％ compared to the case without an EDZ.
S.Kwon J.S.Kim W.J.Cho
Korea Atomic Energy Research Institute, Daejeon, Korea
国际会议
香港
英文
1-5
2009-05-19（万方平台首次上网日期，不代表论文的发表时间）