..., such as, regression method of geostress, regulating method of stress boundary, fit- ting method of stress function, and so on (Karakus 637 2005 & Kaiser 1990). In large hydropower station, many researches on back-analysis of initial stress field for rockmass near underground power houses have been carried out (Jiang...

... tunnels and the underground testing sites #2 and #3 at the Jinping II hydropower station are buried in the entire Jinping mountain at a maximum depth of 2525 m. The in-situ stress level is very high and the self-weight stress at that depth reaches 66.5 MPa. Many difficulties, such as the breakouts...

... ABSTRACT: Excavation induced stress change is a significant and considerable factor to drive the brittle failure in the underground opening. Rockburst, as a type of brittle failure, has became a great threat to the construction of mining, traffic tunnels, hydropower station etc. With Hoek...