Isamu Hirano

Stochastic block theory for initial support decision of large slope

Abstract Stochastic Block Theory is suggested as the management tool for the decision for initial support of key block before every discontinuity trace of the block has not appeared on slope surface, in other word, in the moment some of the discontinuity traces of the block have appeared. The probability of forming a removable block by the next excavation can be calculated by taking rock joint distribution into account. The applicability of the theory is examined using the joint trace maps.

Prediction Equations for Weathering of Cretaceous Kitakyusyu Granite by Outdoor Exposure Test.

In order to predict the weathering process of rock foundation and rock materials for engineering purpose, fundamental studies have been carrying out to investigate the factor of weathering, changes of some properties and rock deterioration mechanism by weathering.The outdoor exposure tests on Cretaceous Granitic Rock (Kitakyusyu granite) were carried out in this study. The columnar specimens used in this experiment are composed of a series of rocks that include fresh rocks to weathered rocks. Their weathering properties were clarifed by the outdoor exposure, and the regression equations for the deterioration process were obtained as a function of outdoor exposure time. Using these equations, one can predict the weathering process from the initial physical and mechanical indices of rocks.