Nothing in nature stands still forever, including masses of what we think are solid, rock. Earthquakes, landslides, and the collapse of underground structures are the most obvious examples of the rapid and destructive nature of rock mass motions. Rock stress is one important factor that affects these motions and related phenomena. As such, various aspects of rock mass stresses must be studied, and this has driven development of techniques to measure or estimate the in-situ state of stress. Such efforts have been made so far mainly for two purposes of underground construction and earthquake analysis. Works in these two areas have been conducted almost independently of one another in part because of the differences in the depths at which they were traditionally important, i.e. less than one kilometer and more than ten kilometers, respectively. In recent years, however, geomechanical approaches applied to oil and gas or geothermal exploitation are becoming common place. For the mining industry, deeper and higher stress mining has become more important. Consequently rock stress and its effect on the mechanical behavior of rock masses at intermediate depths have drawn much attention. Accordingly to such advancements in this area, we will hold the 6th International Symposium on In-situ Rock Stress to promote the knowledge exchange and discussion on the topics related to rock stress at a wide variety of depth ranging from tens of meters to tens of kilometers. Currently, earthquake, whether they be natural or induced, are key issues and keynote lectures are planned on the 2011 great Tohoku-Oki earthquake (Mw 9.0) that severely damaged parts of Northern Japan.
Takatoshi ITO, Prof.
General Chair for RS2013
Institute of Fluid Science, Tohoku Univ., Japan
|Stress change due to the 2011 Tohoku-Oki earthquake:
s1, s3; red, blue arrows
(courtesy of Prof. A. Hasegawa, Tohoku Univ.)