AE法を利用した初期地圧測定とその適用例

抄録

A Large scale underground cavern, such as an underground power station, can be designed and executed rationally, if the initial stress condition of the site is known. Authors have carried out fundamental studies on the detection of initial stress using Acoustic Emission technique (Kaiser effect) by which the stress history of a rock mass can be estimated. In this paper, the characteristics of Kaiser effect on rock material have been investigated and the two or three dimentional principal stress condition has been estimated. It has been found that (1) the stress determined by the Kaiser effect is not always identical to the maximum stress of rock; (2) the Kaiser effect is a time-dependent phenomenon; (3) the initial stress estimated by AE method is not always equal to the initial stress estimated by the overcoring method in some field measurements.