Stydy on Improved Procedure for Determination of Three Dimensional Distributions of the Initial Rock Stresses (Second Report)

Mizuta, Yoshiaki*; Kaneko, Katsuhiko*; Matsuki, Koji*; Sugawara, Katsuhiko*; Sudo, Shigeaki*

In the fiscal year of 2002, our committee achieved the following work items during the contract period, from August 28th, 2002 to February 7th, 2003. Confirm mutual understanding with respect to the geological / geometrical data provided from Tono Geoscience Center and exchange procedure for taking those into each numerical models. The numerical models by Finite Element Method and Finite Difference Method were built taking strata data into account. A problem accompanying to back analysis for inhomogeneous modeling was brought up. A new 3D Boundary Element Method Code in which integrations to calculate the influence coefficients are carried out analytically and thus, the solutions with high accuracy can be given faster. Three examples of determination procedures, wide region model by FEM, small region model by FEM and intermediate region model by FDM were introduced. This is the report as the results of the studies mentioned above.