ABSTRACT
In this paper, we have demonstrated that the rock mass mechanical properties of the basalt lava was evaluated by the numerical analysis with a homogenization theory. The basalt lava around Tokuyama underground power house at the upper part of Ibi River in Gifu prefecture, Japan, included cracks and fractures with slickenside and specific deforming structures that would be formed in the process of the plate accretion and faulting. It was feared that the deformation structures would adversely affect the stability of the underground power house. Therefore, we evaluated the mechanical properties of the rock mass including the structure by a method using a numerical analysis based on homogenization theory, and then performed excavation analysis of the underground power house with the calculated mechanical properties and compared the analysis result with the observed displacement around the underground power house. As a result, it was showed that the method was practical for the evaluation of such rock-mass properties.
